Drug interactions between Lipitor and Reyataz
Results for the following 2 drugs: |
|
|---|---|
| Lipitor (atorvastatin) | |
| Reyataz (atazanavir) | |
Interactions between your selected drugs
atorvastatin ↔ atazanavir
Applies to:Lipitor (atorvastatin) and Reyataz (atazanavir)
ADJUST DOSE: Protease inhibitors (PIs), particularly ritonavir, may significantly increase the plasma concentrations of atorvastatin. The mechanism is PI inhibition of CYP450 3A4 metabolism. In 14 healthy volunteers, ritonavir (400 mg twice a day) and saquinavir (soft gelatin capsule 400 mg twice a day) given for 14 days increased the mean peak plasma concentration (Cmax) and area under the concentration-time curve (AUC) of atorvastatin plus atorvastatin acid (given as atorvastatin 40 mg once a day for 4 days) by 148% and 73%, respectively. In 16 study subjects, amprenavir (given as fosamprenavir 1400 mg twice a day for 2 weeks) increased Cmax and AUC of atorvastatin (10 mg once a day) by 304% and 130%, respectively. These values were increased 184% and 153%, respectively, with ritonavir-fosamprenavir (700 mg-100 mg twice a day). High levels of HMG-CoA reductase inhibitory activity in plasma are associated with an increased risk of musculoskeletal toxicity, including myopathy and rhabdomyolysis, which may be accompanied by acute renal failure secondary to myoglobinuria and may result in death.
MANAGEMENT: Atorvastatin may be used with caution and close monitoring in patients treated with protease inhibitors, although the lowest possible dosage should be used. Fluvastatin and pravastatin are probably safer alternatives, since they are not metabolized by CYP450 3A4. All patients treated with HMG-CoA reductase inhibitors should be advised to promptly report any unexplained muscle pain, tenderness, or weakness, particularly if accompanied by malaise or fever. Therapy should be discontinued if creatine kinase is markedly elevated in the absence of strenuous exercise or if myopathy is otherwise suspected or diagnosed.
See also...
Drug Interaction Classification
The classifications below are a guideline only. The relevance of a particular drug interaction to a specific patient is difficult to determine using this tool alone given the large number of variables that may apply.
| Major | Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. |
| Moderate | Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. |
| Minor | Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan. |
Do not stop taking any medications without consulting your healthcare provider.
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