Magnets, How do they work? (Mechanisms of Action/Pharmcodynamicostuffs)

Question 1

Define drug ‘efficacy’

Answer 1

The degree to which a drug is able to induce maximal effects

Question 2

Define drug ‘potency’

Answer 2

The amount of drug required to produce 50% of maximal response that the drug is capable of inducing.

Question 3

Morphine and codeine are both capable of relieving post-op pain. A smaller dose of morphine than codeine is required to achieve the effect. Therefore, morphine is more ________ than codeine.

Answer 3

potent

Question 4

What is the EC50 (Effective Concentration 50%)?

Answer 4

The concentration of drug which induces a specified clinical effect in 50% of the subjects to which the drug is administered

Question 5

What is the LD50 (Lethal Dose 50%)?

Answer 5

The concentration of drug which induces death in 50% of the subjects to which the drug is administered

Question 6

What is the therapeutic index?

Answer 6

A measure of the safety of a drug. Calculated by dividing the LD50 by the ED50

Question 7

What is the margin of safety?

Answer 7

The margin between therapeutic and lethal doses of a drug

Question 8

Prescribing drugs without consideration for the patient profile is substandard care. The patient profile each of the following considerations: (6 of them)

Answer 8

Age, Pregnancy status, Smoking and drinking habits, Liver or kidney disease, Pharmacogenetics, Drug interactions, Psychosocial factors

Question 9

Why is knowing a patient’s smoking and drinking habits important for prescribing any medication?

Answer 9

Both smoking and drinking induce P450 liver enzymes. This accelerates the metabolism of a number of drugs. In some cases, the result is a lower-than-expected drug concentration leading to decreased therapeutic effectiveness. Prodrugs, however, might be metabolized to more active forms. In some cases, the active drug reaches toxic concentrations

Question 10

What psychosocial factors should go into your size-up of the patient profile?

Answer 10

Consider the cost, ease of administration, dose schedule, and level of patient responsibility.

Question 11

Name the BACTERICIDAL drugs that work at the cell wall

Answer 11

1. Penicillins
2. Cephalosporins
3. Vancomycin
4. Bacitracin
5. Carbapenems
6. Monobactams
7. Daptomycin

Question 12

The mechanism of action of the penicillins is

Answer 12

inhibition of bacterial cell growth by interference with cell wall synthesis. Penicillins bind to and inactivate the penicillin-binding proteins (PBPs)

Question 13

MOA of fluoroquinolones?

Answer 13

Strong inhibitors of DNA gyrase and topoisomerase IV. These enzymes are critical in the process of supercoiling DNA. Without them, bacteria cannot replicate

Question 14

MOA of macrolides?

Answer 14

inhibition of bacterial synthesis by binding to the 50S ribosomal subunit