Pharmacokinetics, Pharmacodynamics, Pharmacology of Autonomic nervous system drugs, Autocoids

11.    Ephedrine:

a.     can act directly on alpha and beta receptors.

b.    is poorly absorbed orally.

c.    is resistant to the action of penicillamase.

d.    is readily effective against S.aureus.

12.    Propranolol:

a.     is a beta-1 and beta-2 adrenergic receptor blocker.

b.     should be used in care in patients receiving insulin.

c.     is contra-indicated in asthmatic patients.

d.     is extensively metabolized in the liver.

13.    The effects of beta-adrenergic blockade by propranolol include:

a.     decreased release of adrenaline from adrenal medulla.

b.     antagonism of the effects of noradrenaline on the heart.

c.     decrease of symptoms in thyrotoxic patients.

d.     bronchoconstriction in asthmatic patients.

14.   Histamine:

a.     is metabolized by enzyme in the gut.

b.     is chiefly excreted unchanged.

c.     is released in anaphylaxis. 

d.     stimulates nerve endings especially those mediating pain and itching.

15.    Side effects of chlorpheniramine:

a.      drowsiness.

b.      sweating.

c.      dry mouth.

d.      miosis.

16.    Atropine and hyoscine:

a.      at therapeutic dose may cause dryness of mouth and inhibit sweating.

b.      differ in their CNS effects.

c.      are contraindicated in glaucoma.

d.      are competitive antagonists of acetylcholine at nicotinic sites.

17.    Di-isopropyl fluorophosphate:

a.      inactivates cholinesterase irreversibly.

b.      penetrate the CNS because of its high lipid solubility.

c.      causes pupillary constriction.

d.      can be absorbed through the skin and mucous membrane.

18.    Atropine:

a.      acts competitively at muscarinic receptors.

b.      dilates the pupil.

c.      paralyses accommodation in the eye.

d.      causes dryness of the mouth. 

19.    Hypotension caused by D-tubocurarine is attributed to:

a.      its action on the CNS.

b.      its blocking action on sympathetic ganglia.

c.      the release of histamine.

d.      its direct vasodilator action.

20.    Noradrenaline:

a.      acts on beta-adrenergic receptors on the heart.

b.      action is terminated mainly by re-uptake.

c.      re-uptake is inhibited by the TCAs.

d.      is released from adrenergic nerve endings by tyramine.

<< Last Page                       Answers                             Next Page >>