Uses
Posaconazole is used to prevent certain fungal infections in patients who have severely weakened immune systems (such as patients who have had chemotherapy). It belongs to a class of drugs known as azole antifungals. It works by stopping the growth of fungi.
How To Use
Read the Patient Information Leaflet if available from your pharmacist before you start taking posaconazole and each time you get a refill. If you have any questions, ask your doctor or pharmacist.
Take this medication by mouth with or without food as directed by your doctor, usually once daily. Do not crush or chew delayed-release tablets. Doing so can release all of the drug at once, increasing the risk of side effects. Swallow the whole tablet without crushing or chewing.
The length of treatment is based on your medical condition.
This medication works best when the amount of medicine in your body is kept at a constant level. Take this drug at evenly spaced intervals.
The tablet and suspension forms of posaconazole may deliver different amounts of medication. Do not switch between the different forms of this medication without your doctor's permission and directions.
Tell your doctor if you have severe diarrhea or vomiting. Posaconazole may not work as well.
Side Effects
Nausea, vomiting, diarrhea, headache, abdominal pain, dizziness, trouble sleeping, or stomach upset may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.
Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor right away if you have any serious side effects, including:
- unusual tiredness
- easy bruising/bleeding
- weakness
- muscle cramps
- mental/mood changes
- swelling of the ankles/feet
- signs of infection (such as chills, fever)
- vaginal bleeding
- shortness of breath
- increased thirst/urination
Get medical help right away if you have any very serious side effects, including:
- fast/irregular heartbeat
- severe dizziness
- fainting
Posaconazole has rarely caused very serious (possibly fatal) liver disease. Tell your doctor right away if you develop symptoms of liver disease, including:
- nausea/vomiting that doesn't stop
- yellowing eyes/skin
- dark urine
- severe stomach/abdominal pain
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:
- rash
- itching/swelling (especially of the face/tongue/throat)
- severe dizziness
- trouble breathing
Posaconazole can commonly cause a mild rash that is usually not serious. However, you may not be able to tell it apart from a rare rash that could be a sign of a severe allergic reaction. Get medical help right away if you develop any rash.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Precautions
Before taking posaconazole, tell your doctor or pharmacist if you are allergic to it; or to other azole antifungals (such as 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 rarely cause 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. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis). Alcohol may 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 unknown if this drug passes into breast milk. Consult your doctor before breast-feeding.
Drug Interactions
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Other medications can affect the removal of posaconazole from your body, which may affect how posaconazole works. Examples include efavirenz, 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), certain benzodiazepines (such as midazolam), dronedarone, ergot alkaloids (such as ergotamine, dihydroergotamine), pimozide, quinidine, rivaroxaban, sirolimus, certain "statin" drugs (such as lovastatin, simvastatin), venetoclax, among others.
Many drugs besides posaconazole may affect the heart rhythm (QT prolongation), including pacritinib, among others.
Overdose
If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Alberta residents can call PADIS (Poison and Drug Information Service) 24 hours a day at 1-800-332-1414. Canada residents can call a provincial poison control center.
Notes
Do not share this medication with others.
This medication has been prescribed for your current condition only. Do not use it later to prevent another infection unless your doctor tells you to.
Lab and/or medical tests (such as liver function, blood mineral levels such as calcium, magnesium, potassium) should be done before you start using this medication and while you are using it. Keep all medical and lab appointments. Consult your doctor for more details.
Missed Dose
If you miss a dose, take it as soon as you remember. If it is within 12 hours of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.
If you have questions about missing a dose or you don't have more medication, contact your healthcare provider or pharmacist.
Storage
Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
