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Clinical Review Glucocorticoids in Clinical Practice Eileen G. Holland, PharmD, and A. Thomas Taylor, PharmD Augusta and Athens, Georgia The many unique features of glucocorticoids makes therapy with these steroids challenging. The anti-in- flammatory potency, relative mineralocorticoid activity, plasma half-life, and route o f administration o f the syn- thetic cortisol preparations are compared. Because they produce profound anti-inflammatory and immunosup- pressive effects, exogenously administered glucocorti- coids are effective therapy for a variety o f diseases and conditions. The appropriate dosing regimen is an ade- quate dose administered for a sufficient period to pre- cipitate an acceptable response. It is impossible to pre- dict the regimen that will suppress the hypothalamic- pituitary-adrenocortical (HPA) axis and thereby increase the risk of developing adrenal insufficiency during periods of stress. Until recovery o f the axis is complete, patients require daily physiologic replace- ment doses; high-dose supplemental therapy may be required during a major illness or surgery. Once there are signs of improvement, the dosing regimen should be adjusted to a single morning dose, then to an alter- nate-day regimen, and, as soon as possible, the steroid should be discontinued. This tapering process main- tains disease suppression while minimizing toxicity; however, it is often complicated by exacerbation of the disease and withdrawal symptoms. Potential complica- tions associated with glucocorticoid therapy are numer- ous, involve all organ systems, and are potentially more devastating than the HPA axis suppression. / Pam Pract 1991; 32:512-519. For several decades glucocorticoids have been used ex- tensively in the management o f a wide spectrum o f diseases. First isolated in 1935 by Kendall and co-workers, cortisone was administered to a woman with severe rheumatoid arthritis in 1948. Although the clinical improvement was dramatic, certain side effects became apparent.1 During subsequent years, much information concerning the bio- chemistry, pharmacology, tissue effects, toxicity, and clini- cal use o f glucocorticoids has accumulated. The mecha- nisms by which glucocorticoids exert their anti- inflammatory and immunosuppressive effects remain elusive, however. This article provides information neces- sary for clinicians to properly prescribe glucocorticoids. Hypothalamic-Pituitary- Adrenocortical Axis The hypothalamic-pituitary-adrenocortical (HPA) axis controls the amount of cortisone present in normal cir- Submitted, revised, October 5, 1990. From the University o f Georgia College o f Pharmacy, Athens, and Department o f Fdmily M edicine, M edical College o f Georgia, Augusta. Requestsfo r reprints should be addressed to Eileen G. Holland, PharmD, F I 1076, M edical College o f Georgia, Augusta, Georgia 30912. © 1991 Appleton & Lange ISSN 0094-3509 culation (Figure 1). A hypothalamic hormone, corti- cotropin-releasing factor, stimulates the release of] adrenocorticotropic hormone (ACTH), or corticotropin, | which stimulates the adrenal cortex to secrete cortisol. Through a negative-feedback mechanism, an increase in circulating cortisol results in inhibition of corticotropin -1 releasing factor and subsequent ACTH secretion.3 In, humans, glucocorticoids are synthesized in a series of1 reactions that converts cholesterol to pregnenolone, to| progesterone, and finally to cortisol. In adults, about 20 mg of cortisol is secreted daily from the adrenal cortex. This secretion is considered the physiologic replacement amount. In children, about 12 mg/m2 is secreted daily. The normal diurnal cycle results in peak cortisol levels in the morning with a gradual tapering off by mid to late afternoon.1’3 During periods of acute stress, the adrenal cortex can secrete up to 300 mg of cortisol per day.4-5 Glucocorticoid Preparations and Routes of Administration Several synthetic analogues o f cortisol are currently avail- able for systemic use. The anti-inflammatory potency, relative mineralocorticoid activity, and plasma half-life ot 512 The Journal of Family Practice, Vol. 32, No. 5, 1991
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Page 1: Glucocorticoids in Clinical Practice · 2019-01-24 · Numerous creams, ointments, and gels are available for direct application to inflamed or pruritic areas of the skin. Ophthalmic

Clinical Review

Glucocorticoids in Clinical PracticeEileen G. Holland, PharmD, and A. Thomas Taylor, PharmDAugusta and Athens, Georgia

The many unique features o f glucocorticoids makes therapy with these steroids challenging. The anti-in­flammatory potency, relative mineralocorticoid activity, plasma half-life, and route o f administration o f the syn­thetic cortisol preparations are compared. Because they produce profound anti-inflammatory and immunosup­pressive effects, exogenously administered glucocorti­coids are effective therapy for a variety o f diseases and conditions. The appropriate dosing regimen is an ade­quate dose administered for a sufficient period to pre­cipitate an acceptable response. It is impossible to pre­dict the regimen that will suppress the hypothalamic- pituitary-adrenocortical (HPA) axis and thereby increase the risk o f developing adrenal insufficiency during periods o f stress. Until recovery o f the axis is

complete, patients require daily physiologic replace­ment doses; high-dose supplemental therapy may be required during a major illness or surgery. Once there are signs o f improvement, the dosing regimen should be adjusted to a single morning dose, then to an alter­nate-day regimen, and, as soon as possible, the steroid should be discontinued. This tapering process main­tains disease suppression while minimizing toxicity; however, it is often complicated by exacerbation of the disease and withdrawal symptoms. Potential complica­tions associated with glucocorticoid therapy are numer­ous, involve all organ systems, and are potentially more devastating than the HPA axis suppression./ Pam P ract 1991; 32:512-519.

For several decades glucocorticoids have been used ex­tensively in the management o f a wide spectrum o f diseases. First isolated in 1935 by Kendall and co-workers, cortisone was administered to a woman with severe rheumatoid arthritis in 1948. Although the clinical improvement was dramatic, certain side effects became apparent.1 During subsequent years, much information concerning the bio­chemistry, pharmacology, tissue effects, toxicity, and clini­cal use o f glucocorticoids has accumulated. The mecha­nisms by which glucocorticoids exert their anti­inflammatory and immunosuppressive effects remain elusive, however. This article provides information neces­sary for clinicians to properly prescribe glucocorticoids.

Hypothalamic-Pituitary- Adrenocortical AxisThe hypothalamic-pituitary-adrenocortical (HPA) axis controls the amount o f cortisone present in normal cir-

Submitted, revised, October 5, 1990.

From the University o f Georgia College o f Pharmacy, Athens, and Department o f Fdmily M edicine, M edical College o f Georgia, Augusta. Requests fo r reprints should be addressed to Eileen G. Holland, PharmD, F I 1076, M edical College o f Georgia, Augusta, Georgia 30912.

© 1991 Appleton & Lange ISSN 0094-3509

culation (Figure 1). A hypothalamic hormone, corti­cotropin-releasing factor, stimulates the release of] adrenocorticotropic hormone (ACTH ), or corticotropin, | which stimulates the adrenal cortex to secrete cortisol. Through a negative-feedback mechanism, an increase in circulating cortisol results in inhibition o f corticotropin-1 releasing factor and subsequent ACTH secretion.3 In, humans, glucocorticoids are synthesized in a series of1 reactions that converts cholesterol to pregnenolone, to | progesterone, and finally to cortisol.

In adults, about 20 mg o f cortisol is secreted daily from the adrenal cortex. This secretion is considered the physiologic replacement amount. In children, about 12 mg/m2 is secreted daily. The normal diurnal cycle results in peak cortisol levels in the morning with a gradual tapering off by mid to late afternoon.1’3 During periods o f acute stress, the adrenal cortex can secrete up to 300 mg o f cortisol per day.4-5

Glucocorticoid Preparations and Routes o f AdministrationSeveral synthetic analogues o f cortisol are currently avail­able for systemic use. The anti-inflammatory potency, relative mineralocorticoid activity, and plasma half-life ot

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Glucocorticoids Holland and Taylor

Figure 1. The hypothalamic-pituitary-adrenocortical (HPA) axis. The normal diurnal cycle of cortisone secretion begins with the release o f corticotropin releasing factor from the hypothalamus which stimulates adrenocorticotropin (ACTH) secretion from the pituitary. A CTH stimulates the adrenals to release cortisol at a rate of about 20 mg per day with peak cortisol levels occurring in the morning. Through negative feedback, an increase in circulating cortisol (or its synthetic analogues) results in inhibition of this cycle.

commonly prescribed preparations are provided in Table 1. Since glucocorticoids are pharmacologically active un­til metabolized, agents with a prolonged half-life are associated with both increased anti-inflammatory po­tency and a greater degree o f H P A axis suppression.1’4 Nevertheless, when these agents are administered in equivalent anti-inflammatory doses, neither qualitative nor quantitative differences in the anti-inflammatory ef­fects are evident.6 Neither hepatic nor renal dysfunction appears to alter the pharmacokinetic disposition o f glu­cocorticoids.7 Cortisone and hydrocortisone are rarely employed for long-term anti-inflammatory therapy be­cause they have the highest sodium-retaining properties.1

Prednisone and cortisone lack glucocorticoid activ­ity until they are converted to prednisolone and cortisol m the liver.1.8 Consequendy, in patients with acute hep­atitis or active chronic liver disease, availability o f the active compound is assured by administering pred­nisolone rather than prednisone.1’7’9 Similarly, an intra­ocular injection o f cortisone or its direct application to the skin is ineffective in the treatment o f systemic disease

Table 1. Comparison of Glucocorticoid Preparations

Equivalent Anti­inflammatory

Dose (mg)

Sodium-RetainingPotency

PlasmaHalf-life

(min)

Short-actingCortisone 25 2 + 30Hydrocortisone 20 2 + 9 0

(cortisol)

Intermediate-actingPrednisone 5 1 + 60Prednisolone 5 1 + 20 0Methylprednisolone 4 0 180Triamcinolone 4 0 300

Long-actingDexamethasone 0 .75 0 20 0Betamethasone 0 .6 -0 .7 5 0 3 0 0 +

because cortisone must be activated to cortisol by the liver.8

Glucocorticoids can be administered through a va­riety o f routes to elicit either a systemic or local response (Table 2). Intravenous administration rapidly delivers high concentrations o f the drug and is generally reserved for acute situations. Intramuscular administration is not often recommended because these depot preparations prolong HPA axis suppression.7 I f tolerated by the pa­tient, oral administration is the preferred route. Because o f both rapid and complete absorption from the gastro­intestinal tract, dosing o f oral and parental glucocorti­coids is equivalent.10

Numerous products are available for topical and local administration. Local administration o f glucocorti­coids permits the delivery o f high doses o f active drug to the target tissue while minimizing the effects on other tissues and suppression o f the HPA axis.1’3’7 With all o f these preparations, however, there is the potential for systemic absorption o f the glucocorticoid and subse­quent HPA axis suppression.

Numerous creams, ointments, and gels are available for direct application to inflamed or pruritic areas o f the skin. Ophthalmic drops and ointments are used in con­junctivitis and other inflammatory conditions o f the eyes. Inhaled preparations provide a direct, local action in the lungs and are used in patients with bronchial asthma who require chronic treatment with corticosteroids in con­junction with other therapy. Intranasal preparations pro­vide symptomatic relief o f seasonal or perennial rhinitis and may prevent the recurrence o f nasal polyps. Intra- articular, intrasynovial, and intralesional administrations o f glucocorticoids provide local effects with minimal systemic toxicity. These local injections are usually re­served for bursitis, tendinitis, and epicondylitis o f the knee, ankle, wrist, elbow, shoulder, hip, and phalangeal

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Table 2. Routes of Administration o f Common Glucocorticoid Products

Drug PO IV IM s c IA ID Top Inh Nasal Rect Ophth OticCortisone X — X ___ ___ ___ ____ ____ ___ ___ — ~Hydrocortisone X X X X X — X — — X ___ xPrednisone X — — — — — — — — — ___

Prednisolone X X X — X — — — — — XMethylprednisolone X X X — X — X — — — —

Triamcinolone X — X — X X X X — — ___

Dexamethasone X X X — X — X X X — XBetamethasone X X X — X X X — — — ___

Flunisolide — — — — — — — X X — ___

Beclomethasone — — — — — — — X X — — __

PO— oral; IV — intravenous; IM — intramuscular; SC— subcutaneous; IA — intra-articular; ID — intraderm al; Top— topical; Inh—respiratory inhaler; Nasal—intranasal solution R ea—rectal enema; Ophth— ophthalmic.

joints. Glucocorticoid retention enemas are used as ad­junctive therapy in the treatment o f ulcerative colitis, c4-7

Mechanism o f ActionThe precise mechanism by which glucocorticoids exert their anti-inflammatory and immunosuppressive effects is complex.11 The administration o f glucocorticoids results in a transient increase in the number and proportion o f circulating neutrophils while the concentration o f other classes o f leukocytes is diminished or unchanged.6’11 E l­evation o f the neutrophil count is due to a combination o f an accelerated release o f mature neutrophils from the bone marrow and their decreased migration from the blood.1 It has been proposed that suppressed leukocyte accumulation at the site o f inflammation is the principal mechanism by which glucocorticoids exert their anti­inflammatory and immunosuppressive effects.1’6 Addi­tionally, glucocorticoids interfere with the function o f the leukocytes present at the site o f inflammation.7

H PA Axis Suppression

Administration o f exogenous glucocorticoids in amounts greater than that needed for physiologic replacement results in HPA axis suppression and subsequent adrenal atrophy.12 Because the demand for cortisol cannot be met by atrophic adrenal glands, potentially serious and even fatal complications arise when steroids are discon­tinued abruptly or a patient becomes acutely ill.2 Indeed, suppression o f the HPA axis will generally not be evident until the patient is subjected to major stress, such as that associated with surgery, trauma, infection, or severe emotional disturbances.7

Following the daily administration o f the equivalent o f 20 to 30 mg o f prednisone for 1 to 4 weeks, biochem­ically demonstrable H PA axis suppression may persist for 1 year or more after treatment is discontinued.13 After

discontinuing the prolonged (more than 1 year) admin­istration o f supraphysiological doses o f glucocorticoids, the functions o f the hypothalamus and pituitary glands arc the first to recover, about 5 to 9 months following therapy.14 About 9 to 12 months are required for the adrenocortical response to return to normal. Following withdrawal o f prolonged doses o f glucocorticoids, at least 12 to 16 months must elapse before the complete return o f normal homeostatic function, including respon­siveness to stress.8’14 The time course o f recovery from smaller doses is not known.

In patients with decreased adrenal function due to ! atrophy, adrenocortical insufficiency can be avoided by administering daily physiological replacement doses (5| mg prednisone or its equivalent) until the adrenal func­tion normalizes. In addition, for at least 6 months aftert discontinuing glucocorticoids, supraphysiological doses1 o f steroids should be administered during periods of acute stress.2-4’7

Patients with documented or presumed decreased ad- j renal function should carry identification with them to alert medical personnel o f their requirements for supplemental' glucocorticoids during an emergency'. In addition, patients with poor adrenal function who are at increased risk for j becoming acutely ill because o f concomitant disease states, social situations, or environmental conditions should be) given a prefilled syringe containing 4 mg o f dexamethasone, to be injected intramuscularly if they are unconscious or unable to take medication by mouth.2-3

Indications for GlucocorticoidsGlucocorticoids are prescribed for a variety' o f inflamma­tory and immune-mediated diseases (Table 3). This di­verse assortment o f conditions affects nearly all organ1 systems and involves multiple etiologies. The goal of j glucocorticoid therapy is not to eradicate the causative

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Table 3. Disorders for Which Glucocorticoids May Be Beneficial

RheumatologicAnkylosing spondylitis BursitisTenosynovitis Acute gouty a rth ritis Rheumatoid a rth ritis Osteoarthritis DermatomyositisPolymyalgia rheum atica Systemic lupus ery them atosus Acute rheum atic card itis Mixed connective tissue

disease Polymyositis Vasculitidies

DermatologicPemphigusBullousDermatitis herpetiformis Severe erythema multiforme

(Stevens-Johnson syndrome)

Mycosis fangoides Severe psoriasis Angioedema Contact dermatitis Atopic dermatitis

OphthalmicAllergic conjunctivitis KeratinsHerpes zoster ophthalmicusIritisUveitisOptic neuritis

AllergicD rug hypersensitivity Serum sickness Urticarial transfusion

reactions

RespiratorySymptomatic sarcoidosis Severe asthma BerylliosisFulminating or disseminated

tuberculosis Aspiration pneumonitis Allergic rhinitis

HematologicIdiopathic thrombocytope­

nia purpuraAutoimmune hemolytic

anemiaOrgan transplant rejection Immune mediated

cytopenias Erythroblastopenia

EdematousIdiopathic nephrotic

syndrome Cerebral edema

Gastrointestinal Ulcerative colitis Crohn’s disease

MiscellaneousChronic active hepatitisMeningitisHypercalcemiaAdrenal cortical insufficiency

factor, but to minimize the sequelae while allowing the disease to run its natural course.7

Designing a Therapeutic RegimenDesigning an appropriate regimen is complicated. The preferred therapeutic strategy' is dictated by the specific disease, the glucocorticoid preparation, and the pa­tient,1.7 For example, short-term glucocorticoid therapy of life-threatening diseases such as status asthmaticus provides dramatic improvement with few complications, while prolonged therapy o f chronic inflammatory condi­tions can be associated with serious side effects.1 Conse­quently, the severity o f the disease, the anticipated dose ®d duration o f therapy, and the immediate and future prognosis o f the patient should be considered in deter­mining the appropriateness o f glucocorticoid therapy. Also, other therapeutic modalities that can delay the use of steroids or decrease the required dose should be used. Examples include aerosolized glucocorticoids for asth­

matic patients and nonsteroidal anti-inflammatory agents in patients with rheumatoid arthritis.

The efficacy o f specific regimens for certain condi­tions is proven; however, alternative agents, doses, and durations o f therapy have not been studied to compare the efficacy o f various other regimens. Consequently, there are no definitive guidelines that outline proper therapy in specific diseases. T o assist clinicians in the daily therapeutic decision process, further research is needed to determine the agent o f choice, the dosage, and the optimal duration o f therapy for specific diseases.

A suitable dosing regimen for glucocorticoids in­cludes a sufficient quantity o f the drug administered over an adequate period to bring the inflammatory or immu­nologic reaction under control.1 Therefore, the total daily dose is variable, depends on many factors, and can range from grams o f methylprednisolone in acute organ transplantation rejection to 60 to 100 mg o f prednisone in various hypersensitivity or autoimmune disorders. Ad­mittedly, recommendations for administering glucocor­ticoids are vague; however, there are several important points to consider when prescribing these agents. Each o f these is discussed separately.

Initiating TherapyOnce the decision has been made to administer gluco­corticoids, therapy should be initiated with a dose suffi­cient to control the disease process.1’7 By initiating ther­apy with a low dose, such as 10 to 15 mg o f prednisone, one risks failure to induce optimal anti-inflammatory control. Consequently, to establish control, the dose must be increased and, by the end o f therapy, a greater total dose may have been administered.7 In general, patients with severe inflammatory illnesses known to be sensitive to glucocorticoids can be placed into remission with 1 mg/kg/d o f prednisone, administered in one to three divided doses.1

The risk o f HPA axis suppression and toxicity in­creases when multiple daily doses are administered or when long-acting agents are employed; however, toxicity does not develop if use is continued only until the acute disease process is alleviated.1 Conversely, a single daily dose appears to be as effective as divided daily doses in controlling certain diseases, including rheumatoid arthri­tis, systemic lupus erythematosus, and polyarthritis.8 The preferred regimen employs a short- or intermediate-act­ing agent administered once daily, in the morning. The early morning dose more closely resembles the natural diurnal cycle o f cortisol secretion and results in less HPA axis suppression.1-4’7

Once there are subjective and objective signs o f improvement, the dose and dosing interval should be

X _______________________________ ________ __ ________________________________________________

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adjusted so that disease suppression will be maintained with fewest complications.1 However, dosage reduction is chiefly determined and limited by the presence or absence o f an exacerbation o f the underlying disease.

Converting to Alternate-Day Therapy

Following conversion to a single daily dose, an effective way to continue the tapering process is to convert to alternate-day administration. Based on the hypothesis that the anti-inflammatory effects o f glucocorticoids per­sist longer than the undesirable metabolic effects, alter­nate-day therapy provides a sufficient quantity o f steroid to suppress disease activity while avoiding many o f the complications associated with daily therapy.14'8 Indeed, numerous studies have reported that alternate-day ther­apy resulted in the prevention or amelioration o f adverse effects and H PA axis suppression while providing thera­peutic effectiveness similar to that o f daily therapy.8

Although alternate-day therapy can maintain remis­sion in a disease process, this regimen is usually not capable o f inducing a remission in patients with fulmi­nant disease.4>1S Therefore, alternate-day therapy should be considered a prophylaxis against exacerbations o f a disease process that was originally controlled by daily steroid therapy.1 The demonstrable benefits o f alternate- day therapy occur only when steroids are used for a prolonged duration. I f the anticipated duration o f ther­apy is less than several weeks, there is no rationale for alternate-day therapy.8

To convert a patient to alternate-day therapy, the lowest daily steroid requirement should be determined. The optimal every-other-day dose is 2Vi to 3 times the minimal daily dose. Generally, an intermediate-acting agent is administered as a total daily morning dose.3'15 The dose on the “o ff” day should be gradually tapered by the equivalent o f 2 .5 to 5 mg o f prednisone until the patient is on a true alternate-day regimen. Although the average daily dose on the alternate-day regimen may be IV2 times the previous daily dose, long-term complica­tions will be minimized.1'7

The tapering o f the alternate-day dose can continue until the minimum dose sufficient to control the disease process is reached or until the drug is discontinued. Ideally, the regimen will be converted to alternate-day therapy after the first week o f treatment and, if possible, the glucocorticoid will be discontinued after another 3 weeks.3 Too rapid tapering o f glucocorticoid therapy, however, frequently results in reexacerbation o f the dis­ease.16 The tapering process can be complicated not only by exacerbations o f the underlying disease process, but also by withdrawal syndromes, which may mimic disease activity. 1>7'8>12 Typical glucocorticoid withdrawal symp­

toms include fatigue, weakness, arthralgia, anorexia, nau- sea, fever, weight loss, headache, desquamation of the skin, orthostatic dizziness and hypotension, fainting, dys- i pnea, and hypoglycemia.1- 3'7 These symptoms are tran­sient and may be minimized by a more gradual tapering ̂ o f the steroids.

Predicting HPA Axis SuppressionClinical data do not provide adequate information to predict which glucocorticoid regimen places patients at risk for developing adrenocortical insufficiency under the stress o f surgery or severe illness. Laboratory data indi- * cate that 1 to 2 weeks o f therapy can result in adrenal insufficiency.8 Since the current data do not satisfactorily answer this practical question, more research is needed to define the situations in which patients are at greatest risk for developing HPA axis suppression.

Based on the available information, however, the following general guidelines may assist the clinician. Pa­tients receiving the equivalent o f 20 to 30 mg of pred­nisone daily for more than 1 week should be suspected of! having HPA axis suppression. Patients receiving morn­ing doses closer to the physiological range should be suspected o f having HPA axis suppression after approx-1 imatcly 1 month o f continuous therapy. I f administered early in the day, physiological replacement doses of glu­cocorticoids are unlikely to cause HPA axis dysfunction.®) M ost important, the degree o f HPA axis suppression j may not be predictable; it depends on the patient, the disease state, and the dose, duration, frequency, time, and route o f administration o f the glucocorticoid.2-4

1Testing the H PA AxisWhen HPA axis suppression is suspected, the clinician has two alternatives. One is to treat the patient as though adrenocortical insufficiency is present. The other is to test | the pituitary, hypothalamic, and adrenocortical reserves, j A rapid test o f adrenal function measures the 8:00 am fasting plasma cortisol level. Once a level greater than i 280 nmoPL (10 jug/dL) is sustained, therapy maybe discontinued.3 Effective provocative tests include insulin- induced hypoglycemia, metyrapone, lysine-vasopressin, I and an ACTH test.8 The first three tests are perhaps more. sensitive indicators o f HPA reserve, but are traumatie and cumbersome, and require hospitalization. The I ACTH test correlates best with adrenocortical response to clinical stress.

The ACTH test is a reliable method of evaluating1 the HPA system before surgery in glucocorticoid-treatcJ [ patients. The maximal response o f the plasma-cortisol

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G lucocorticoids Holland and Taylor

level to ACTH corresponds to the maximal plasma- cortisol level observed during the induction o f general anesthesia and surgery.8'13 Also, for patients receiving physiological replacement doses, this test enables the physician to periodically assess the function o f the adre­nal glands and determine when recovery is complete.

After withholding glucocorticoid therapy for 12 to 24 hours and determining a baseline plasma cortisol level at 8:00 a m , 250 /rg o f synthetic A CTH (cosyntropin) is administered intramuscularly. A repeat plasma cortisol is measured in 30 to 60 minutes. A normal response in­cludes an increase in plasma cortisol o f greater than 170 nmol/L (6 pg/dL) to a level o f more than 550 nmol/L (20 gg/dL). An insufficient elevation o f cortisol levels indicates adrenal insufficiency and the need for continued steroid supplementation during periods o f stress.2- 4-8'13

Complications and ContraindicationsAlthough the primary focus o f glucocorticoid therapy is on potential HPA axis suppression, decades o f experience suggest that it is not as great a problem as is generally believed and is less hazardous than the other serious toxicides associated with steroid therapy13 (Table 4). In addition, while potential complications o f glucocorticoid therapy are numerous and involve all organ systems, it is important to emphasize that when steroids are used properly, complications can be minimized.

It is virtually impossible to predict which toxicities will appear in an individual; however, some patients may be at increased risk for certain side effects. The adverse effects can be classified as those that develop acutely and those that develop after long-term administration. Acute side effects such as central nervous system changes, fluid and electrolyte disorders, gastrointestinal upset, and im­paired glucose tolerance may occur during the induction of anti-inflammatory control or during crisis therapy.7 Generally, when high doses o f steroids are tapered or stopped, these short-term effects lessen or disappear. Long-term side effects are more insidious in onset, occur in patients who receive daily steroids for months or longer, and are less likely to improve quickly after the drugs are discontinued.7 Examples include a Cushingoid appearance, growth retardation, hypertension, os­teoporosis, and pancreatitis. Most important, the fre­quency and severity o f all steroid-related complications can be reduced considerably by converting to alternate- day therapy.1

It is frequently stated that glucocorticoid therapy is associated with an increased prevalence o f peptic ulcer or its recurrence or complications. In 1976, a retrospective analysis o f 42 prospective, controlled investigations in-

Table 4. Adverse Effects Associated with Glucocorticoid Therapy

Adrenocortical excess Buffalo hump Hirsutism Truncal obesity

Musculoskeletal effects Muscle wasting Muscle pain Muscle weakness Delayed wound healing Osteoporosis Aseptic necrosis Growth retardation

Increased susceptibility to infection Opportunistic pathogens: fungus,

virus, bacteria, parasite Recurrence o f tuberculosis Recurrence o f chickenpox Immunosuppression, anergy

Cardiovascular and fluid disturbances Hypernatremia Edema Hypokalemia Hypokalemic alkalosis Hypertension Hypercalciuria

Ocular effectsPosterior subcapsular cataractsExophthalmusGlaucoma

Endocrine effects Hypercorticism AmenorrheaDecreased glucose tolerance HyperglycemiaUnmask genetic predisposition to

diabetes mellitus H PA axis suppression

Gastrointestinal effects Nausea Vomiting AnorexiaIncreased appetite Diarrhea Constipation Abdominal distension Pancreatitis Gastric irritation Ulcerative esophagitis Intestinal perforation

Nervous system effects Headache Vertigo Insomnia Restlessness Ischemic neuropathy E E G abnormalities Seizures Euphoria M ood swings Depression Anxiety PsychosesPseudomotor cerebri

Dermatologic effects AcneSkin atrophy and

thinning StriaeIncreased sweating Facial erythema Angioedema Petechiae Ecchymosis Easy bruisibility Allergic dermatitis Urticaria

volving 5331 patients randomly selected to receive ste­roid (or ACTH) therapy or no therapy was conducted to determine whether this association is valid.17 Proven peptic ulcers were found in 1.3% o f the 2985 steroid- treated patients and in 0.8% o f the 2346 control patients (P > .05). In addition, neither hemorrhage nor perfora­tion o f peptic ulcer occurred significantly more often in the steroid-treated group (all groups < 0.3% ). In 1983, a similar analysis o f 71 investigations involving 5961 patients was conducted.18 The overall incidence o f diag­nosed ulcers was 1.8% in the steroid-treated patients and 0.8% in the control group (P < .001).

Obviously, this is a controversial topic, and it is difficult to determine whether there is a clinically impor­tant association between glucocorticoid therapy and pep­tic ulcer formation. Owing to their ability to induce tissue atrophy, however, glucocorticoids probably en­hance the ulcerogenic potential o f environmental factors and o f other drugs. The risk o f ulcerogenesis depends on

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the underlying disease and the dose administered. Risk appears to increase i f the duration o f therapy is longer than 30 days or if a total dose greater than 1000 mg o f prednisone is administered.17 Therefore, unless patients are receiving ulcerogenic agents, concomitant adminis­tration o f antiulcer agents is not warranted. In addition, the efficacy o f antiulcer therapy in preventing these ulcers has not been established.

The influence o f glucocorticoids on host resistance to infection is also controversial. Patients with normal host defenses who are treated with low to moderate doses o f glucocorticoids do not have an increased risk o f infection.1 Even these doses, however, can activate tu­berculosis in patients with a subclinical course.2 Con­versely, high-dose steroids (defined as more than 50 mg o f prednisone daily or its equivalent) for more than 2 weeks may result in opportunistic infections including those caused by Aspergillus, cytomegalovirus, Pneumocys­tis carin ii, and herpes zoster.6'7 One problem in deter­mining the effect o f glucocorticoids on host resistance to infection is that many patients receiving steroids already have decreased resistance due either to their disease state or to concomitant immunosuppressive therapy.1'7 Alter­nate-day therapy may reduce the risk o f infection.4'6’8

There are no absolute contraindications for the use o f glucocorticoids. As always, however, the potential risks and benefits o f therapy should be addressed, partic­ularly if any o f the following conditions are present: systemic fungal infections, diabetes mellitus, peptic ulcer disease, psychiatric difficulties, osteoporosis, or chronic infections such as tuberculosis.1

Monitoring Long-term Corticosteroid TherapyIt is essential that patients receiving corticosteroids on a long-term basis be monitored closely to detect early signs o f toxicity. Early recognition o f adverse effects may per­mit correction o f the problem or prevent further progres­sion to serious disease. A simple flow sheet that indicates when to perform physical examinations and laboratory tests may be devised to detect potential adverse effects associated with long-term corticosteroid therapy (Figure 2).

ConclusionsAlthough glucocorticoids are frequently employed for the treatment o f numerous inflammatory and immuno­logic disorders, there are no definitive guidelines that

Monitoring Sheet for Long Term Corticosteroids Use

Dale Dat. Data Dal. Date Dl„

P r e p a r a t io n a n d d o s e

M o n th ly

W e i g h t 1B l o o d p r e s s u r e

B lo o d g lu c o s e

E le c t r o ly t e s a n d c r e a t in e

C o m p l e t e b lo o d c o u n t ( C B C ) "O r a l m u c o s a e x a m

E v e r y 6 m o n t h s

C h e s t x -r a y

P P D w it h c o n t r o l

O p h t h a l m o lo g y c o n s u lt

R e c t a l e x a m / h e m o c c u lt

A s a p p r o p r ia te

U p p e r g a s t ro in t e s t in a l ( U G I ) s e r ie s

L a t e ra l t h o r a c ic s p in e x - r a y

S u p p le m e n ta l th e r a p y :

p o t a s s iu m

d iu re t ic

e s t r o g e n

c a lc iu m

v it a m in D

is o n ia z id

1

Figure 2. Example of a patient form used to ensure careful j monitoring of long-term corticosteroid use.

)outline appropriate therapeutic strategies. For each dis­ease, many questions remain unanswered, including the agent o f choice, the appropriate dose and duration of therapy, and the best method for drug discontinuation. It is evident, however, that dosages should be sufficient to produce an appropriate anti-inflammatory response, be kept at the lowest effective level, and be tapered as soon as possible.

References

1. Kehrl JH , Fauci AS. The clinical use o f glucocorticoids. Ann Allergy 19 8 3 ; 5 0 :2 -1 0 .

2. Koch-Weser J. Withdrawal from glucocorticoid therapy. N Engl 1 Med 19 7 6 ; 2 9 5 :3 0 -2 .

3. Kountz DS. An algorithm for corticosteroid withdrawal. AmF» j Physician 1 9 8 9 ; 3 9 :2 5 0 -4 .

4 . Heifer E L , Rose LI. Corticosteroids and adrenal suppression, characterizing and avoiding the problem. Drugs 1989; 38:831-; 45 .

5. Click M . Glucocorticosteroid replacement therapy: a literatim review and suggested replacement therapy. Oral Surg Oral Mf Oral Pathol 1989 ; 6 7 :6 1 4 -2 0 .

6. Fauci AS, Dale D C, Balow JE . Glucocorticosteroid therapy: mat anisms o f action and clinical considerations. Ann Intern 1 L 1 9 7 6 ; 8 4 :3 0 4 -1 5 .

7. Claman H N . Glucocorticosteroids II: the clinical responses, Hffif Pract 1 9 8 3 ; Ju ly :1 4 3 -5 1 .

518 The Journal o f Family Practice, Vol. 32, No. 5.

Page 8: Glucocorticoids in Clinical Practice · 2019-01-24 · Numerous creams, ointments, and gels are available for direct application to inflamed or pruritic areas of the skin. Ophthalmic

Glucocorticoids

8 Axelrod L. Glucocorticoid therapy. Medicine 1 9 7 6 ; 5 5 :3 9 -6 5 .9 Powell LW , Axelsen E . Corticosteroids in liver disease: studies on

the biological conversion o f prednisone to prednisolone and plasma protein binding. Gut 1 9 7 2 ; 1 3 :6 9 0 -6 .

10 Ratto D, Alfaro C , Sipsey J, et al. Are intravenous corticosteroids required in status asthmaticus? JAM A 1 9 8 8 ; 2 6 0 :5 2 7 - 9 .

11 Claman HN. Glucocorticosteroids I: anti-inflammatory mecha­nisms. Hosp Pract 1 9 8 3 ; July: 1 2 3 -3 4 .

12 Mortimer RH . Adrenal corticosteroid replacement therapy. Med J ' Aust 1985; 1 4 3 :3 5 0 -4 .

13. Christy NP. H PA failure and glucocorticoid therapy. Hosp Pract 1984; July :77-89.

H. Graber AL, Ney R L , Nicholson W E , et al. Natural history of pituitary-adrenal recovery following long-term suppression with corticosteroids. J Clin Endocrinol Metab 1 9 6 5 ; 2 5 :1 1 -6 .

15 Laurens RG, Honig EG . Corticosteroids in treatment o f asthma.' South Med J 1986 ; 7 9 :1 5 4 4 -5 3 .

16. Lederle FA, Pluhar R E , Joseph AM , et al. Tapering o f corticoste­roid therapy following exacerbation o f asthma: a randomized, double-blind, placebo-controlled trial. Arch Intern Med 1987 ; 147:2201-3.

17. Conn HO, Blitzer B L. Nonassociation o f adrenocorticosteroid therapy and peptic ulcer. N Engl J Med 19 7 6 ; 2 9 4 :4 7 3 -9 .

18. Messer J, Reitman D , Sacks H S, et al. Association o f adrenocor­ticosteroid therapy and peptic-ulcer disease. N Engl J Med 1983 ; 309:21-4.

The Journal of Family Practice, Vol. 32, No. 5, 1991

YOCON-Yohimbine HCI

Description: Yohimbine is a3a-15a-20B-17a-hydroxy Yohimbine- 16a-car-boxylic acid methyl ester. The alkaloid is found in Rub- aceae and related trees. Also in Rauwolfia Serpentina (L) Benth. Yohimbine is an indolalkylamine alkaloid with chemical similarity to reserpine. It is a crystalline powder, odorless Each compres­sed tablet contains (1/12 gr.) 5.4 mg of Yohimbine Hydrochloride. Action: Yohimbine blocks presynaptic alpha-2 adrenergic re­ceptors, Its action on peripheral blood vessels resembles that of reserpine, though it is weaker and of short duration. Yohimbine's peripheral autonomic nervous system effect is to increase para­sympathetic (cholinergic) and decrease sympathetic (adrenergic) activity. It is to be noted that in male sexual performance, erection is linked to choiinergic activity and to alpha-2 adrenergic blockade which may theoretically result in increased penile in­flow, decreased penile outflow or both.

Yohimbine exerts a stimulating action on the mood and may increase gnxiety Such actions have not been adequately studied or related to dosage although they appear to require high doses of the drug. Yohimbine has a mild anti-diuretic action, probably via stimulation of hypothalmic centers and release of posterior pituitary hormone.

Reportedly, Yohimbine exerts no significant influence on cardiac stimulation and other effects mediated by B-adrenergic receptors, its effect on blood pressure, if any, would be to lower it; however no adequate studies are at hand to quantitate this effect in terms of Yohimbine dosage.Indications: YoconB is indicated as a sympathicolytic and myd- riatric. l t may have activity as an aphrodisiac.Contraindications: Renal diseases, and patient’s sensitive to the drug. In view of the limited and inadequate information at hand, no (precise tabulation can be offered of additional contraindications. Warning: Generally, this drug is not proposed for use in females and certainly must not be used during pregnancy. Neither is this drug proposed for use in pediatric, geriatric or cardio-renal patients with gastric or duodenal ulcer, history. Nor should it be used in conjunction with mood-modifying drugs such as antide­pressants, or in psychiatric patients in general.Adverse Reactions: Yohimbine readily penetrates the (CNS) and produces a complex pattern of responses in lower doses than required to produce peripheral a-adrenergic blockade. These include, anti-diuresis, a general picture of central excitation including elevation of blood pressure and heart rate, increased motor activity, irritability and tremor. Sweating, nausea and vomiting are common after parenteral administration of the d rug .'” 2 Also dizziness, headache, skin flushing reported when used orally 1 ;iDosage and Administration: Experimental dosage reported in treatment of erectile impotence.1 J 1 tablet (5.4 mg) 3 times a day, to adult males taken orally. Occasional side effects reported with this dosage are nausea, dizziness or nervousness. In the event of side effects dosage to be reduced to V% tablet 3 times a day, followed by gradual increases to 1 tablet 3 times a day. Reported therapy not more than 10 weeks.2 How Supplied: Oral tablets of Yocon* 1/12 gr 5.4 mg in bottles of 100’s NDC 53159-001-01 and 1000’s N0C 53159-001-to. References:1. A. Morales et al., New England Journal of Medicine: 1221.

November 12.1981.2. Goodman, Gilman — The Pharmacological basis of Thera­

peutics 6th ed.. p. 176-188. McMillan December Rev. 1/85.3. Weekly Uroiogicai Clinical let­

ter, 27:2, July 4,1983.4. A. Morales et a l., The Journal

Of Urology 128:45-47.1982.

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