nirmatrelvir/ritonavir

HMG-CoA reductase inhibitors lovastatin, simvastatin ↑ lovastatin ↑ simvastatin Co-administration contraindicated due to potential for myopathy including rhabdomyolysis [see Contraindications (4) ] . If treatment with PAXLOVID is considered medically necessary, discontinue use of lovastatin and simvastatin at least 12 hours prior to initiation of PAXLOVID, during the 5 days of PAXLOVID treatment, and for 5 days after completing PAXLOVID.

Mechanism: This medicine stops your body from breaking down simvastatin, which can lead to high levels that cause serious muscle damage.

What to do: Stop taking simvastatin at least 12 hours before starting Paxlovid and do not start it again until 5 days after you finish the treatment.

HMG-CoA reductase inhibitors lovastatin, simvastatin ↑ lovastatin ↑ simvastatin Co-administration contraindicated due to potential for myopathy including rhabdomyolysis [see Contraindications (4) ] . If treatment with PAXLOVID is considered medically necessary, discontinue use of lovastatin and simvastatin at least 12 hours prior to initiation of PAXLOVID, during the 5 days of PAXLOVID treatment, and for 5 days after completing PAXLOVID.

Mechanism: This medicine blocks the way your body processes lovastatin, which can cause the drug to reach dangerous levels and hurt your muscles.

What to do: You should stop taking lovastatin 12 hours before starting Paxlovid and wait 5 days after finishing Paxlovid before taking it again.

Pulmonary hypertension agents (PDE5 inhibitors) sildenafil (Revatio ® ) ↑ sildenafil Co-administration of sildenafil with PAXLOVID is contraindicated for use in pulmonary hypertension due to the potential for sildenafil associated adverse events, including visual abnormalities hypotension, prolonged erection, and syncope [see Contraindications (4) ] . sildenafil, tadalafil, vardenafil ↑ sildenafil ↑ tadalafil ↑ vardenafil Dosage adjustment is recommended for use of sildenafil, tadalafil or vardenafil with PAXLOVID when used for erectile dysfunction.

Mechanism: This combination makes sildenafil stay in your body longer and at higher levels, which can cause your blood pressure to drop too low.

What to do: Avoid this combination if you take sildenafil for high blood pressure in the lungs, or talk to your doctor about a dose change if using it for erectile dysfunction.

Anticonvulsants carbamazepine , phenobarbital, primidone, phenytoin ↓ nirmatrelvir/ritonavir Co-administration contraindicated due to potential loss of virologic response and possible resistance [see Contraindications (4) ] .

Mechanism: Carbamazepine makes your body get rid of the antiviral medicine too quickly, which prevents it from working against the virus.

What to do: Do not take these medicines together because the antiviral treatment will not be able to fight the infection properly.

Antimycobacterial rifampin, rifapentine ↓ nirmatrelvir/ritonavir Co-administration contraindicated due to potential loss of virologic response and possible resistance.

Mechanism: Rifampin causes the body to break down nirmatrelvir/ritonavir too quickly, which lowers the amount of medicine in your blood. This can make the treatment less effective and may lead to the virus becoming resistant.

What to do: Do not take these two medications together.