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Aug 25, 2020
( Name(s) : Period: Date: )
Reaction Rates Round Robin
HASPI Medical “COURSE” Lab DRAFT
( http://www.kksblog.com/wp-content/uploads/2013/02/Medicine.jpg )Routes of Drug Administration
Although most individuals may be familiar with just a few of these, there are many different ways to take medication. For many over the counter medications, it’s most common to take medicine orally, or administered by mouth. Oral meds come in various forms including different types of pills and liquids that are absorbed into your body through your digestive system. There are even some melt in the mouth meds, which may be absorbed without having to wait to get all the way down to your stomach.
Sometimes, a common medication people take orally needs a different delivery system. Vomiting for instance, could mean a person can’t keep a medication in their stomach long enough for it to be absorbed into their body. Numerous medications are taken anally, via suppository and absorbed through the thin walls of the large intestines.
A number of lotions and creams exist that are called topical. These are usually directly applied on the area that needs the medication. Examples include certain steroids that used in healing purposes and anti-itch medicines.
Transdermal methods include an adhesive patch with various drugs that are absorbed directly through the skin. Some forms of transdermal meds include pain medications and nicotine for those quitting smoking.
Some people take medicine through inhalation. Common inhaled meds include those that treat asthma and nasal sprays that treat allergies.
One of the more common and quickest ways to take medicine usually requires a doctor or nurse’s help. Medication may be delivered intravenously (IV) or by infusion. IV drugs go directly into the bloodstream, which can make them work quickly and be most effective. Injections or shots are another way to take medications and these may be injected into muscles, under the skin, directly into bone marry, or into the blood stream.
Pharmacology is the branch of medicine that focuses on the study of drugs and the effects they have on certain biochemical functions. Pharmacologists are constantly looking for ways to improve how medications work, develop more sophisticated methods for delivering drugs into the body, and better ways to target specific sites at which we want the drugs to work. In doing this, they need to pay particular attention to the pharmacodynamics of the drug, or the effect a drug has on the body. They also focus on the pharmacokinetics of a drug, most often abbreviated PK. Pharmacokinetics focuses on how the concentration of a drug changes as it moves through different compartments of your body, from the moment it is administered all the way till the point it is eliminated from your body. After a drug is administered it undergoes a number of chemical reactions that allow it to be broken down, absorbed, distributed to various organs, utilized to alter certain biochemical reactions, and eventually eliminated. Simple changes in drug concentrations, how the drug is administered, where the drug is administered, or even interactions with other drugs taken can have profound effects on its efficacy.
This lab consists of six stations in which you and your group members will manipulate common household medications to recognize how simple changes in surface area, temperature, stirring and mixing, interactions with catalysts and enzymes, and concentrations can change a drug’s rate of reaction.
( Review Questions Of the different routes of drug administration, which ones have you used before? Why can’t all medications be taken orally? What is the advantage of taking a drug intravenously? Define pharmacodynamics. Define pharmacokinetics. What are some things that can change the effectiveness of a drug once it has been administered in the body? )
( Station 1: Surface Area )
( https://www.dexilant.com/Content/Images/section4_tortoiseHare.png )Learning Target:
You should be able to recognize the effect of surface area on the rate of a reaction.
( Figure 0 : The two substances can react more quickly with more surface area because all of this reactant is exposed. Figure 0 : If one substance is not ground up, only the outer portion can react, slowing the reaction down. )A reaction occurs because of collisions between particles. If two reactants never come in contact, a reaction cannot take place. However when two reactants collide more often, reactions can proceed at a greater rate. When a substance has more surface area more reactant is exposed allowing for more collisions between particles at any given time. See Figures 1 & 2.
Some medications can be designed in pill tables or capsules to dissolve a drug over time in order to be released slower and steadier into the bloodstream. These “time-release” medications offer the advantage of being taken at less frequent intervals than immediate-release variations of the same drug.
Different medicines absorb into the bloodstream at different rates because of the surface area of the drug that is exposed. In time-release medications some parts of the drug are completely exposed and can be absorbed into the body immediately. Others parts of the drug may be coated with a buffer substance that needs to be eaten away at various rates by your stomach acids so that the medicine can be absorbed in increments over a period of time. This allows multiple doses of medication to be given in one tablet.
If a patient crushes a time release capsule it can be deadly, or at least very dangerous because all of the medication will be absorbed at once, possibly leading to an overdose.
Station 1 Pre-Lab Questions:
1. Why do reactions occur?
2. What increases the rate of reaction?
3. Why does a chemical with less surface area have a slower reaction rate?
4. What does crushing the sample do to the surface area?
5. How do time release medications work?
6. What do you think would happen if you crushed a time release capsule before taking it?
Make a Hypothesis:
If a substance has more surface area it will....
· 2 beakers
· 1 mortar and pestle
· 1 tablet of alka-seltzer per group
1. Take one tablet of alka seltzer and break it in half
2. Grind up one half of the tablet, leave the other half of the tablet the way it is.
3. Pour 100 mL of water into two beakers.
4. At the same moment add each half of the alka seltzer tablet to the two beakers.
Station 1 Conclusion Questions:
1. Which sample reacts more quickly? Why?
2. Which sample has more surface area?
Finish this sentence:
When a chemical has more surface area the reaction is ____________________________________ (faster or slower)
( Station 2: Temperature )Learning Target:
You should be able to recognize the effect of temperature on the rate of reaction.
Chemical reactions can only take place when reactants come in contact with one another in the correct orientation. If reactants do not collide, they cannot react. If reactants collide, but the orientation is not correct, they cannot react. When a substance is heated up, the molecules move more quickly, increasing the number of possible collisions, and therefore increasing the chances of a reaction occurring.
( Successful Collision Leading to a Chemical Reaction B B + + B B B B + Unsuccessful Collision With No Chemical Reaction Occurring B B B B A A A A A A A A A A A A B B )
( http://wps.prenhall.com/wps/media/objects/3932/4026649/st2_03.jpg )Drugs are created by pharmaceutical manufacturers as stable compounds that are not intended to breakdown (react) until they are taken up the body. But like the food we intake for nourishment spoils and rots if we do not consume it in a certain amount of time, drugs can break down and lose their efficacy, or ability to produce a desired effect over time. This is why the drugs we buy over the counter and the medications that are prescribed by the doctor have an expiration date. Exposing drugs to heat can speed up this breakdown process. Keeping medications in a cool, dry place is essential to keeping them working properly. Pharmaceutical manufacturers recommend most of their products be stored at a controlled temperature of 68-77°F (20-25 °C). Some drugs require refrigeration to keep from going bad, and in some cases need to be placed in the freezer. A temperature over 86°F (30 °C) can cause the medication to decompose more quickly and have a lower effectiveness or even stop working all together.
( http://www.drugcite.com/label/unzipped/20101214_f60a672d-8d6d-4d67-9a47-5547357e7b5b/lipitor-08.jpg )
Station 2 Pre-Lab Questions:
1. What must happen in order for two reactants to react?
2. What effect does temperature have on the motion of reactants in a chemical reaction?
3. What can cause a medicine to decompose more quickly?
4. Where should medications be stored?
Make a Hypothesis:
Increasing the temperature will cause a reaction to….
· 2 beakers
· 1 larger hot plate with a beaker of hot water on it
· 1 tablet of Alka-Seltzer
1. Fill one beaker half way with tap water at room temperature.
2. Fill the other beaker half way with w