1) The neurotransmitters acetylcholine and norepinephrine are digested by enzymes that are located at the axon synapse or within the axon terminal of the neurons.
a)What are the names of these different types of enzymes?
b)Where are they located and what is the result of their enzymatic activity?
2) Explain how the Investigational New Drug process works as well as the four different phases of clinical trials. Why are some drugs still taken off the market after approval by the FDA?
3) A single IV injection of 100 mg drug with a half-life of 4 hours is administered to a young adult.
a) Plot drug concentration versus time on a graph making certain to clearly label.
b) How long will it take to eliminate > 95% of the drug?
c) If the volume of distribution is 4L, what is the clearance of the drug?
4) Many drugs are metabolized in the liver through the microsomal metabolizing system.
a) What specific enzymes are involved in this metabolism?
b) What are the main functions of these enzymes?
c) What are some factors that can contribute to individual drug metabolism variation? Explain.
5) Think of an emergency situation requiring immediate and intense physical exertion.
a) List as many body organs as you can and predict the desired level of activity [increased or decreased].
b) Which neurotransmitter would produce these effects and through what receptors?
6) It is interesting that a drug can produce a therapeutic effect and an undesired side effect in one situation, and that the same drug side effect may be considered a therapeutic effect in another situation. Explain this phenomenon using the drug promethazine as an example.
7) A patient brought into the emergency room is experiencing severe hypotension. Blood pressure reads 90/50.
a) What class of drugs is indicated for treatment and why?
b) What precautions should be observed when these drugs are administered?
c) What would be the first indication that too much drug has been administered?
8) Only certain drugs are capable of crossing the blood brain barrier.
a) How is the blood brain barrier different than barriers found in other areas of the body? Be specific.
b) What properties of drugs will make it more likely to cross the blood brain barrier? Explain your answers.
9) A 32-year-old, presents to the Emergency Department by ambulance with vomiting, confusion, salivation, and respiratory distress. The patient states that he was feeling fine until today when I started getting ill. He then vomits. During a physical exam you record the following information: Heart rate 45; Blood pressure 90/60; Respiratory rate 25; Temperature 36.6C; Pupils constricted. During your exam, 4 more ambulances arrive with patients with similar symptoms. You find out they were all riding in the same care on the Red Line when they began feeling ill.
a) What do you feel is happening and why?
b) Would you expect their symptoms to improve over time? Why or why not?
c) What drug would you prescribe to treat these patients and why?
10) Betty has diabetes and asthma. She also has developed high blood pressure, for which doctor just prescribed propranolol. One of your duties as a physician’s assistant is to make sure patients are not prescribed drugs that are contraindicated because of other health problems.
a) What should you tell the doctor about Betty’s prescription for propranolol and why?
b) Is there a more appropriate drug for Betty? Explain you answer.
