Paxlovid Drug Interactions and Contraindications
Contraindicated Medications
- The American College of Cardiology and other guideline societies recommend avoiding the use of statins, such as lovastatin, simvastatin, and atorvastatin, with Paxlovid due to the increased risk of rhabdomyolysis 1
- Sedatives/hypnotics, including oral midazolam and triazolam, are contraindicated with Paxlovid due to the increased risk of prolonged sedation 1
- Antipsychotics, such as quetiapine, should be avoided due to the increased risk of toxicity 1
- Cardiovascular drugs, including alfuzosin, amiodarone, quinidine, and salmeterol, are contraindicated with Paxlovid 2, 3
- Pulmonary hypertension drugs, such as sildenafil, should be avoided when used for pulmonary arterial hypertension 1
- Ergot derivatives, cisapride, astemizole, and terfenadine are also contraindicated with Paxlovid 2, 3
Enzyme Inducers
- Strong CYP3A4 inducers, including carbamazepine, phenytoin, phenobarbital, rifampicin, St. John's wort, and enzalutamide, are contraindicated as they reduce nirmatrelvir exposure and compromise antiviral efficacy 2, 3
Medication Review
- The guideline society recommends consulting drug interaction databases, such as the Liverpool COVID-19 Drug Interaction tool, for comprehensive medication review before prescribing Paxlovid 1
Paxlovid and Cyclobenzaprine Interaction
Clinical Management Strategy
- The American College of Physicians recommends reducing cyclobenzaprine dose by 50% during the 5-day Paxlovid course to minimize the risk of excessive sedation and anticholinergic effects, with ritonavir's CYP3A4 inhibition persisting for several days after discontinuation 4
Alternative Considerations
- The Liverpool COVID-19 Drug Interaction tool suggests considering alternative muscle relaxants such as methocarbamol, which is not metabolized by CYP3A4, for patients requiring multiple interacting medications during Paxlovid treatment 4