Pharmacokinetics, Pharmacodynamics, Pharmacology of Autonomic nervous system drugs, Autocoids
1. The apparent volume of distribution of a drug
a. is usually larger for a basic drug than an acidic drug.
b. is obtained by dividing the dose administered by its free concentration in the plasma.
c. is inversely related to its elimination half-life
d. may be reduced in cardiac failure.
2. Binding of drugs to plasma proteins show the following characteristics:
a. the bound drug fraction is pharmacologically active.
b. a drug with a larger volume of distribution is more likely to cause overdosage effects than when displaced from plasma protein binding.
c. drug which is bound strongly to plasma protein will also be strongly bound to tissues.
d. binding capacity can be reduced in advanced liver disease.
3. Drugs administered by the oral route show the following characteristics:
a. for most drugs absorption is by passive diffusion.
b. for most drugs the dissolution rate is the rate limiting step.
c. acidic drugs are mainly absorbed from the stomach.
d. basic drugs dissolve more readily in the intestinal than in stomach fluid.
4. The apparent volume of distribution of a drug:
a. is a ratio indicating the relative distribution of the drug between plasma and its target site.
b. is greater if it is more extensively bound to tissues than to plasma proteins.
c. is directly related to its plasma half-life.
d. is fairly constant over a wide dose range.
5. Acetylcholine:
a. has an ester group in its structure.
b. is inactivated by both acetylcholinesterase and plasma pseudocholinesterase.
c. is released at the pre-ganglionic nerve endings.
d. produces a decrease in the force of cardiac contraction.
6. D-tubocurarine:
a. is well absorbed from the GIT.
b. may produce significant ganglion blockade in large doses.
c. actions can be reversed by neostigmine.
d. has been shown to cause histamine release.
7. Propranolol:
a. has intrinsic agonist properties.
b. is a relative specific beta one agonist.
c. can cause bronchial constriction in asthmatic patients.
d. is used in essential hypertension.
8. Histamine causes:
a. increased capillary permeability.
b. gastric hyper-activity.
c. bronchoconstriction.
d. hypotension.
9. The following are physiological antagonists of histamine acting on bronchial smooth muscle:
a. adrenaline.
b. salbutamol.
c. acetylcholine.
d. bradykinin.
10. Antihistamines antagonize histamine action by:
a. stimulating the action of histaminase.
b. competing with histamine for specific receptors.
c. preventing the release of histamine from the cells.
d. enhancing the excretion of histamine.