Kaletra Oral Solution and Lapatinib

In the database of official manuals used in the service creation an interaction registered by statistical results of studies was found, which can either lead to negative consequences for the patient health or strengthen a mutual positive effect. A doctor should be consulted to address the issue of joint drug administration.

Talk to your doctor before using lapatinib together with ritonavir. Combining these medications may significantly increase the blood levels of lapatinib. This can make you more likely to develop side effects such as diarrhea, liver damage, and heart problems including decreased pumping of blood from the heart and abnormal heart rhythm. Call your doctor immediately if you have fever, chills, joint pain or swelling, unusual bleeding or bruising, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, dark colored urine, light colored stools, and/or yellowing of the skin or eyes, as these may be signs and symptoms of liver damage. You should also seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, or fast or pounding heartbeats during treatment with lapatinib. You may not be able to take lapatinib during treatment with ritonavir, or you may need a dose adjustment and/or more frequent monitoring by your doctor to safely use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

GENERALLY AVOID: Coadministration with potent inhibitors of CYP450 3A4 may significantly increase the plasma concentrations of lapatinib, which is primarily metabolized by the isoenzyme. In healthy subjects, administration of lapatinib in combination with the CYP450 3A4 inhibitor ketoconazole (200 mg twice daily for 7 days) resulted in lapatinib systemic exposure (AUC) and half-life that were approximately 3.6- and 1.7-fold, respectively, of the control values.

MANAGEMENT: Concomitant use of lapatinib with potent CYP450 3A4 inhibitors should generally be avoided. If coadministration is required, the manufacturer recommends reducing the lapatinib dosage to 500 mg once a day. Based on pharmacokinetic studies, this dosage is predicted to adjust the lapatinib systemic exposure (AUC) to the range observed without inhibitors. However, clinical data are lacking. Following discontinuation of the potent CYP450 3A4 inhibitor, a washout period of approximately one week should be allowed before the lapatinib dosage is adjusted upward to the indicated dosage (i.e., 1250 mg once a day).

Kaletra Oral Solution

Generic Name: lopinavir / ritonavir

Brand name: Kaletra

Synonyms: Kaletra

What is Kaletra Oral Solution?

Lapatinib

Generic Name: lapatinib

Brand name: Tykerb

Synonyms: n.a.

What is Lapatinib?