Crizotinib and Zithromax Tri-Pak

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.

Using crizotinib together with azithromycin can increase the risk of an irregular heart rhythm that may be serious and potentially life-threatening, although it is a relatively rare side effect. You may be more susceptible if you have a heart condition called congenital long QT syndrome, other cardiac diseases, conduction abnormalities, or electrolyte disturbances (for example, magnesium or potassium loss due to severe or prolonged diarrhea or vomiting). Talk to your doctor if you have any questions or concerns. Your doctor may already be aware of the risks, but has determined that this is the best course of treatment for you and has taken appropriate precautions and is monitoring you closely for any potential complications. You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, or heart palpitations during treatment with these medications, whether together or alone. 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.

MONITOR CLOSELY: Crizotinib can cause concentration-dependent prolongation of the QT interval. Theoretically, coadministration with other agents that can prolong the QT interval may result in additive effects and increased risk of ventricular arrhythmias including torsade de pointes and sudden death. In clinical trials of patients who received crizotinib 250 mg twice daily, 4 of 308 patients (1.3%) developed QTcF (Fridericia-corrected QT interval) greater than or equal to 500 msec, and 10 of 289 patients (3.5%) had an increase in QTcF from baseline greater than or equal to 60 msec. A pharmacokinetic/pharmacodynamic analysis suggested a concentration-dependent increase in QTcF. In general, the risk of an individual agent or a combination of agents causing ventricular arrhythmia in association with QT prolongation is largely unpredictable but may be increased by certain underlying risk factors such as congenital long QT syndrome, cardiac disease, and electrolyte disturbances (e.g., hypokalemia, hypomagnesemia, hypocalcemia). Moreover, the extent of drug-induced QT prolongation is dependent on the particular drug(s) involved and dosage(s) of the drug(s).

MANAGEMENT: Caution is recommended if crizotinib is used in combination with other drugs that can prolong the QT interval. ECG and serum electrolytes, including potassium, magnesium and calcium, should be monitored before starting crizotinib therapy and periodically during treatment. Crizotinib should not be started if baseline QTc is greater than 500 msec. Likewise, treatment should be interrupted in patients who develop Grade 3 QTc prolongation until recovery to less than or equal to Grade 1, then resumed at 200 mg twice daily. In case of recurrence of Grade 3 QTc prolongation, therapy should be withheld until recovery to less than or equal to Grade 1, then resumed at 250 mg once daily. Permanently discontinue crizotinib therapy if Grade 3 QTc prolongation recurs or at any time during treatment if Grade 4 QTc prolongation develops. Patients should be advised to seek prompt medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, lightheadedness, fainting, palpitation, irregular heart rhythm, shortness of breath, or syncope.

Crizotinib

Generic Name: crizotinib

Brand name: Xalkori

Synonyms: n.a.

What is Crizotinib?

Zithromax Tri-Pak

Generic Name: azithromycin

Brand name: Zithromax, Zmax, AzaSite, Azithromycin 3 Day Dose Pack, Azithromycin 5 Day Dose Pack, Zithromax Tri-Pak, Zithromax Z-Pak, Zithromax IV

Synonyms: Zithromax

What is Zithromax Tri-Pak?