Sildenafil (for ED); Tadalafil/HIV Protease Inhibitors; Cobicistat Interactions
This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.
Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
Your protease inhibitor may slow down how quickly your liver processes sildenafil and tadalafil.
What might happen:
Your blood levels of sildenafil or tadalafil may increase and cause harmful effects.
What you should do about this interaction:
Let your healthcare professional (e.g. doctor or pharmacist) know that you are taking these medicines together. If you are taking sildenafil for pulmonary arterial hypertension (PAH), contact your doctor right away. Contact your doctor if you experience a painful or prolonged erection, fainting or dizziness, or changes in vision. The dose of your sildenafil or tadalafil may need adjusting.Your healthcare professionals (e.g. doctor or pharmacist) may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.
- 1.Viagra (sildenafil) US prescribing information. Pfizer Inc. December 14, 2017.
- 2.Reyataz (atazanavir sulfate) US prescribing information. Bristol-Myers Squibb Company March, 2018.
- 3.Prezista (darunavir) US prescribing information. Tibotec Inc. May, 2019. 4.Lexiva (fosamprenavir calcium) US prescribing information. GlaxoSmithKline March, 2019.
- 4.Crixivan (indinavir sulfate) US prescribing information. Merck & Co., Inc. September, 2016.
- 5.Kaletra (lopinavir/ritonavir tablets) US prescribing information. Abbott Laboratories December, 2019.
- 6.Viracept (nelfinavir mesylate) US prescribing information. Agouron Pharmaceuticals, Inc. September, 2016.
- 7.Norvir (ritonavir) US prescribing information. Abbott Laboratories December, 2019.
- 8.Invirase (saquinavir mesylate) US prescribing information. Roche Laboratories, Inc. March, 2019.
- 9.Aptivus (tipranavir) US prescribing information. Boehringer Ingelheim Pharmaceuticals, Inc. June, 2018.
- 10.Revatio (sildenafil citrate) US prescribing information. Pfizer Inc. February 1, 2018.
- 11.Cialis (tadalafil) US prescribing information. Eli Lilly and Company February, 2018.
- 12.Back DJ. Re: 'Pharmacokinetic interactions between sildenafil and saquinavir/ritonavir'. Br J Clin Pharmacol 2000 Aug;50(2):85.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.