Severe. These medicines may interact and cause very harmful effects and are usually not taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
Protease inhibitors may slow down how quickly your liver processes vardenafil. Vardenafil may speed up how quickly your liver processes your protease inhibitor.
What might happen:
The amount of vardenafil in your blood may increase and cause harmful effects. The amount of protease inhibitor in your blood may decrease and it may not work as well.
What you should do about this interaction:
Contact your healthcare professionals (e.g. doctor or pharmacist) right away about using these medicines together. If your are taking indinavir, do not take more than 2.5 mg of vardenafil every 24 hours. If you are taking lopinavir or ritonavir, do not take more than 2.5 mg of vardenafil every 72 hours.Get medical help right away if you experience a painful or prolonged erection. Let your doctor know if you experience fainting, dizziness, or changes in vision.Your healthcare professionals 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.Levitra (vardenafil hydrochloride) Canadian prescribing information. Bayer, Inc. October 24, 2006.
2.Levitra (vardenafil hydrochloride trihydrate) UK summary of product characteristics. Bayer plc December 20, 2006.
3.Levitra (vardenafil hydrochloride) US prescribing information. Bayer Pharmaceuticals Corporation September, 2015.
4.Crixivan (indinavir sulfate) US prescribing information. Merck & Co., Inc. March, 2015.
5.Kaletra (lopinavir/ritonavir tablets) US prescribing information. Abbott Laboratories January, 2013.
6.Norvir (ritonavir) US prescribing information. Abbott Laboratories November, 2015.
7.Aptivus (tipranavir) US prescribing information. Boehringer Ingelheim Pharmaceuticals, Inc. March, 2015.