Clinical consequences of polymorphic acetylation of basic drugs

Area of Science:

• Pharmacogenetics
• Clinical Pharmacology
• Drug Metabolism

Background:

• Drug acetylation is a key metabolic pathway influencing drug efficacy and toxicity.
• Acetylation polymorphism, specifically slow vs. rapid acetylators, leads to inter-individual variability in drug response.
• Understanding these genetic differences is crucial for personalized medicine.

Purpose of the Study:

• To review the clinical consequences of drug acetylation polymorphism.
• To correlate acetylator phenotype with therapeutic and toxic effects of specific drugs.
• To highlight the importance of acetylator status in predicting patient outcomes.

Main Methods:

• Literature review of clinical studies on drug acetylation.
• Analysis of adverse drug reactions and therapeutic responses in slow and rapid acetylators.
• Focus on drugs including procainamide, hydralazine, phenelzine, isoniazid, and salicylazosulfapyridine.

Main Results:

• Slow acetylators exhibit increased risk for procainamide-induced antinuclear antibody and systemic lupus erythematosus (SLE).
• Adverse effects like SLE (hydralazine, spontaneous), drowsiness/nausea (phenelzine), cyanosis/hemolysis (salicylazosulfapyridine), and polyneuropathy (isoniazid) are more common in slow acetylators.
• Rapid acetylators may have a higher incidence of isoniazid hepatitis, while slow acetylators show greater therapeutic response to phenelzine, hydralazine (with beta-blockers), and isoniazid (weekly therapy).

Conclusions:

• Patient acetylator phenotype significantly influences the risk of specific drug toxicities.
• Knowledge of acetylator status can optimize drug selection and dosing for improved therapeutic outcomes.
• Pharmacogenetic profiling holds promise for predicting and mitigating adverse drug events.