What to watch with CYP2C19 and Müdigkeit?

CYP2C19 is a drug-metabolizing enzyme, not a direct 'fatigue gene'. Variants (e.g., *2, *3, *17) affect how quickly you break down certain medications – including clopidogrel, proton pump inhibitors (omeprazole), antidepressants (citalopram, sertraline), and benzodiazepines (diazepam). In 'poor metabolizers', higher drug levels can occur, potentially causing fatigue as a side effect. In 'ultrarapid metabolizers', some drugs may be less effective. There is no strong scientific evidence linking CYP2C19 genotype to fatigue in the absence of medication. Fatigue is multifactorial: sleep, stress, diet, iron deficiency, thyroid issues, infections. A DNA test cannot replace medical evaluation. If you take medications, discuss your genotype with your doctor – dose adjustment may be warranted. Evidence: moderate for drug metabolism, unclear for fatigue as a standalone symptom.