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Tools Health & MedicalCYP450 Pharmacogenomic Checker

Cytochrome P450 Hepatic Clearance Engine Active

CYP450 Pharmacogenomic & Drug-Drug Interaction Checker

Simulate liver enzyme competition across CYP3A4, CYP2D6, CYP2C19, and CYP2C9. Evaluate toxic substrate accumulation, prodrug bioactivation failure, and clinical dosage adjustment guidelines.

Select Co-Administered Medications to Simulate

CPIC & FDA Guidance

Medication #1 (Primary Agent)

Elevated plasma levels increase risk of statin-induced myopathy and rhabdomyolysis.

Medication #2 (Co-Administered Agent)

Strong CYP3A4 inhibitor; markedly spikes plasma concentrations of CYP3A4 substrates.

Primary Metabolic Pathway

CYP3A4 Pathway Analysis

Lipitor + Biaxin

Contraindicated / Severe Hazard

Enzymatic & Pharmacokinetic Mechanism

Potent irreversible/competitive inhibition of intestinal and hepatic CYP3A4 by the co-administered agent.

Observed Clinical Outcomes & Toxicities

Plasma Atorvastatin AUC increases by 400% to 500% (5-fold spike), triggering severe acute myopathy, serum Creatine Kinase (CK) elevation, and potential fatal rhabdomyolysis with acute kidney failure.

Clinical Action Plan & Titration Protocol

•Temporarily withhold Atorvastatin during the short course of Clarithromycin.

•Alternatively, switch to non-CYP3A4 cleared statins (e.g. Rosuvastatin or Pravastatin).

•Counsel patient to report any dark tea-colored urine or severe proximal muscle pain immediately.

Hepatic CYP450 Share

CYP3A4 / CYP3A5 (Largest Share)~50% of all drugs

CYP2D6 (Highly Polymorphic)~25% of all drugs

CYP2C9 & CYP2C19~20% of all drugs

CYP1A2 (Caffeine & Theophylline)~5% of all drugs

Read the Pharmacogenomics Masterclass

Learn how genetic CYP2D6 poor metabolizers and CYP3A4 competitive inhibitors dictate clinical prescription safety.

Read Masterclass Guide

Clinical Pharmacogenomics Notice:Synthesized from Clinical Pharmacogenetics Implementation Consortium (CPIC) and FDA Drug Development and Drug Interactions guidance. Enzymatic interactions represent biochemical models; never discontinue or adjust prescription dosages without consulting a licensed physician or clinical pharmacologist.