Page 43 - Pharmacology Mnemonics and Short Notes

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2. Variation in concentration of endogenous transmitters e.g. -
blockers will slow heart rate markedly in patients with excess

endogenous catecholamines.

3. Alteration in the number or function of receptors, e.g.
thyrotoxicosis increases the number and sensitivity of -
receptors.

- Long use of agonists may decrease the number of receptors

(down-regulation) and this may be responsible for overshoot
phenomena which follows withdrawal of some drugs.

- Long use of antagonists may increase the number of receptors

by preventing down-regulation caused by endogenous
agonists.

6. Dependence

 Habituation: emotional or psychological dependence on the
drug e.g. Tobacco smoking.

 Addiction: both psychological and physical dependence on the
drug e.g. Morphine addiction.

Contents

Pharmacology Mnemonics and Short Notes By Muhammad Ramzan Ul Rehman