| Question | Answer |
| 1. Drugs that remain in the plasma compartment of the body have a volume of distribution (Vd) of:
2. In which ionization state are drugs better able to permeate lipid membranes? | 1. low Vd (3-4L)
2. only the nonionized (uncharged) form crosses membranes |
| 1. In which ionization state are drugs better cleared from the body?
2. What is the ionization of a drug when the pH of the surrounding environment is at the pKa of the drug? | 1. ionized (charged)
2. 50% ionized and 50% nonionized |
| At what pH would the following drugs be ionized?
1. acidic drugs
2. basic drugs | 1. high pH (drug donates a proton to environment)
2. low pH (drug accepts a proton from environment) |
| 1. Where in the body will the following drugs be best absorbed?
1. acidic drugs
2. basic drugs | 1. stomach (low pH so drug is nonionized)
2. small intestine (high pH so drug is nonionized) |
| 1. What is the fastest route of drug absorption?
2. How do you calculate total body water? | 1. inhalation
2. patient's weight x 60% |
| What are the compartments for total body water? | 1. extracellular (14L) which is composed of plasma (3L) and interstitial (11L)
2. Intracellular |
| What is the difference between phase I and phase II types of biotransformation? | 1. phase I: cytochrome P450
2. phase II: conjugation via transferases |
| What is gray baby syndrome? Why is it seen? | 1. chloramphenicol toxicity
2. the drug is metabolized by glucuronidation which has reduced activity in neonates |
| 1. Where is the cell are cytochrome P450 enzymes found?
2. Which cytochrome P450 enzyme metabolizes a majority of the drugs on the market?
3. Which drugs induce SLE-like symptoms? | 1. smooth ER
2. 3A4
3. hydralazine > procainamide > isoniazide |
| Inducers of cytochrome P450: | Queen Barb Steals Phen-phen and Refuses Greasy Carbs Chronically
1. Quinidine
2. Barbiturates
3. St. John's Wort
4. Phenytoin
5. Rifampin
6. Griseofulvin
7. Carbamazepine
8. Chronical alcohol use |
| Inhibitors of cytochrome P450: | Inhibit drinking from a KEG or you'll be Acutely SICk
1. Ketoconazole
2. Erythromycin
3. Grapefruit juice
4. Acute alcohol
5. Sulfonamides
6. Isoniazide
7. Cimetidine |
| 1. What role do beer, red wine and cheese play in drug metabolism?
2. zero-order elimination
3. first order elimination | 1. contain tyramine that is metabolized by phase I monoamine oxidase reaction
2. constant amount eliminated
3. constant fraction eliminated |
| 1. How many half lives does it take to get to steady state?
2. What percentage of steady state is reached after one half-life? | 1. 4-5 half lives
2. 50% |
| What is the effect of mixing a partial agonist and a full agonist? | the partial agonist displaces the full agonist from the receptor and the response is reduced - the partial agonist is acting as an antagonist |
| Which kind of antagonism:
1. competitive antagonism for the same receptor
2. two agonist with opposing action (i.e. vasoconstrictor vs vasodilator)
3. interacts directly with drug to remove it or prevent it from binding target | 1. Pharmacologic antagonist
2. Physiologic antagonism
3. Chemical antagonism |
| How is therapeutic index calculated? | TI = LD50/ED50 (TILE)
dose that is lethal to 50% of the population divided by dose that is effected to 50% of the population |
| 1. How do irreversible inhibitors effect Km and Vmax?
2. How do reversible inhibitors effect Km and Vmax? | 1. decrease Vmax; no effect on Km
2. no effect on Vmax; ↑ Km (less affinity) |
| What is similar of all drugs with "phen" in the name? | 1. lipid soluble
2. cross the blood-brain-barrier
3. liver metabolism |
| 1. Efficacy
2. Potency | 1. Maximal effect a drug can produce
2. Amount of drug needed for a given effect (related to effective dose, ED50) |
| Toxicity Antidotes:
1. Acetaminophen
2. Salicylates
3. Amphetamines
4. Antimuscarinic agent | 1. N-acetylcysteine
2. NaHCO3 (alkalinize urine)
3. NH4Cl (acidify urine)
4. Physostigmine salicylate |
| Toxicity Antidotes:
1. β-blockers
2. Iron
3. Lead
4. Cyanide | 1. glucagon
2. Deferoamine
3. dimercaprol, CaEDTA
4. Nitrite, thiosulfate |
| Toxicity Antidotes:
1. Methemoglobin
2. Methanol
3. Opioids
4. Benzodiazepines | 1. Methylene blue
2. Ethanol
3. Naloxone/naltrexone
4. Flumazenil |
| Toxicity Antidotes:
1. TCAs
2. Warfarin
3. tPA
4. theophylline | 1. NaHCO3 (Alkalinize urine)
2. Vitamin K, fresh frozen plasma
3. aminocaproic acid
4. β-blocker |
| What effect do the following have on efficacy and potency:
1. competitive inhibitors
2. noncompetitive inhibitors | 1. ↓ potency (↑ dose required for effect - same as ↑ Km)
2. ↓ efficacy (less max effect - Vmax) |
