Precautions
Before taking posaconazole, tell your doctor or pharmacist if you are allergic to it; or to other azole antifungals (e.g., ketoconazole); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: liver disease, kidney disease.
Posaconazole may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can infrequently result in serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away.
The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using posaconazole, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions: certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG), family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death).
Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics/”water pills”) or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using posaconazole safely.
This drug may make you dizzy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Avoid alcoholic beverages because they can increase the effects of dizziness and also increase the risk of serious liver problems.
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
Older adults may be more sensitive to the side effects of this drug, especially QT prolongation (see above).
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
It is not known whether this drug passes into breast milk. Consult your doctor before breast-feeding.
Interactions
Many drugs besides posaconazole may affect the heart rhythm (QT prolongation), including amiodarone, dronedarone, pimozide, quinidine, cisapride, among others.
Other medications can affect the removal of posaconazole from your body, which may affect how posaconazole works. Examples include cimetidine, efavirenz, proton pump inhibitors (such as esomeprazole, pantoprazole), rifamycins (such as rifabutin), certain drugs used to treat seizures (such as phenytoin), among others.
This drug can slow down the removal of other drugs from your body, which may affect how they work. Examples of affected drugs include certain alpha blockers (such as alfuzosin, silodosin, tamsulosin), ergot alkaloids (such as ergotamine, dihydroergotamine), certain immunosuppressants (such as cyclosporine, sirolimus, tacrolimus), certain benzodiazepines (such as midazolam, triazolam, alprazolam), certain “statin” drugs (such as atorvastatin, simvastatin, lovastatin), avanafil, eletriptan, eplerenone, lurasidone, ranolazine, rivaroxaban, ticagrelor, tolvaptan, among others.