Page 29 - Pharmacology Mnemonics and Short Notes

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2. Nutritional state as vitamins and minerals are cofactors for the
metabolizing enzymes.
3. Presence of other drugs

a) Activators (Enzyme Inducers)

Some drugs can increase the activity of microsomal enzymes their
ability to detoxicate drugs.
GPRS Cell phone

G  Grisofulvin
P  Phenytoin

R  Rifampicin
S  Smoking
Cell  Carbamazepine
Phone  Phenobarbitone (Benzodiazepines and

barbiturates)

b) Inhibitors (Enzyme Inhibitors)
PC Games
P  P 450 inhibitors

C  Cyclosporine and Cimetidine
G  Grape fruit
A  Antifungals

M  Metronidazole
E  Erythromycin
S  SSRIs

Hepatic First-Pass Metabolism
Metabolism of drugs (usually oral) before reaching the systemic

circulation (pre-systemic metabolism).
Locations liver and GIT linings
How to overcome hepatic first-pass metabolism?

1. Give a loading dose (high first dose).
2. Change route of administration e.g. sublingual or rectal.
Contents 3. Use alternative drug with less hepatic metabolism.

Pharmacology Mnemonics and Short Notes By Muhammad Ramzan Ul Rehman