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:
Ritonavir may slow down how quickly your liver processes vinblastine and vincristine.
What might happen:
The amount of vinblastine or vincristine in your blood may increase and cause serious side effects.
What you should do about this interaction:
Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking these medicines together. Let your doctor know right away if you develop any signs of an infection, such as fever, chills, or persistent sore throat; have severe nausea, vomiting, or diarrhea; muscle weakness; numbness or loss of feeling; abdominal pain; constipation; seizures; or swelling. Your doctor may need to change your HIV therapy or may need to stop it during your chemotherapy.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.Norvir (ritonavir) US prescribing information. Abbott Laboratories March, 2015.
2.Kaletra (lopinavir/ritonavir tablets) US prescribing information. Abbott Laboratories January, 2013.
3.Makinson A, Martelli N, Peyriere H, Turriere C, Le Moing V, Reynes J. Profound neutropenia resulting from interaction between antiretroviral therapy and vinblastine in a patient with HIV-associated Hodgkin's disease. Eur J Haematol 2007 Apr;78(4):358-60.
4.Kotb R, Vincent I, Dulioust A, Peretti D, Taburet AM, Delfraissy JF, Goujard C. Life-threatening interaction between antiretroviral therapy and vinblastine in HIV-associated multicentric Castleman's disease. Eur J Haematol 2006 Mar;76(3):269-71.