What role does CYP2C19 play in Müdigkeit?

CYP2C19 is an enzyme involved in metabolizing many drugs (e.g., certain antidepressants, proton pump inhibitors). Altered enzyme activity (poor, intermediate, rapid, or ultrarapid metabolizer) can affect drug levels in the blood and thereby indirectly contribute to fatigue as a side effect. However, direct genetic effects on exhaustion are not established. The provided context does not include specific studies linking CYP2C19 to fatigue. MyBody-X tests are lifestyle-oriented, not clinical pharmacogenetic tests. Evidence: unclear. Caveat: For persistent fatigue, blood markers (iron, vitamin D, thyroid) and medical evaluation are more relevant than a DNA test.