Voriconazole is used to treat a variety of fungal infections. It belongs to a class of drugs known as azole antifungals. It works by stopping the growth of fungi.

Read the Patient Information Leaflet if available from your pharmacist before you start using voriconazole and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

This medication is given by injection into a vein as directed by your doctor, usually every 12 hours. It should be injected slowly over 1 to 2 hours.

The dosage is based on your medical condition, weight, response to treatment, and other medications you may be taking. Be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

If you are using this medication at home, learn all preparation and usage instructions from your health care professional. Before using, check this product for particles or discoloration. If either is present, do not use the liquid. Learn how to store and discard medical supplies safely.

Infusion reactions may happen during the infusion of this drug. Tell your doctor right away if you have symptoms of infusion reactions such as flushing, fever, sweating, shortness of breath, or nausea.

For the best effect, use this antifungal at evenly spaced times. To help you remember, use this medication at the same times every day.

Continue to use this medication until the full prescribed amount is finished, even if symptoms disappear after a few days. Stopping the medication too early may result in a return of the infection.

Tell your doctor if your condition does not get better or if it gets worse.

See also How to Use section.

Nausea/vomiting and headache 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:

• vision changes (such as blurred vision, color vision changes)
• sensitivity of eyes to light (photophobia)
• eye pain
• signs of kidney problems (such as change in the amount of urine)
• bone/joint pain
• mental/mood changes (such as hallucinations)
• pain/swelling at injection site
• swelling hands/ankles/feet
• easy bruising/bleeding
• unusual skin changes
• signs of your adrenal glands not working well (such as loss of appetite, unusual tiredness, weight loss)

Get medical help right away if you have any very serious side effects, including:

• fast/irregular heartbeat
• severe dizziness
• fainting

Voriconazole may rarely cause serious (possibly fatal) liver problems. Tell your doctor right away if you develop symptoms of liver disease, such as:

• nausea/vomiting that doesn't stop
• loss of appetite
• stomach/abdominal pain
• yellowing eyes/skin
• dark urine

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:

• fever that doesn't go away
• new or worsening lymph node swelling
• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

Voriconazole 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.

Before using voriconazole, tell your doctor or pharmacist if you are allergic to it; or to other azole antifungals (such as itraconazole, 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 your medical history, especially of:

• liver disease
• kidney disease
• heart problems (such as irregular heartbeat)

Voriconazole 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 voriconazole, 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 voriconazole safely.

This drug may cause vision changes. Do not drive, use machinery, or do anything that needs clear vision until you are sure you can perform such activities safely. Do not drive at night.

Avoid alcoholic beverages because they can increase the risk of serious liver problems.

This medication may make you more sensitive to the sun. It may also increase your risk for skin cancer, especially if you use it for a long time. Limit your time in the sun. Avoid tanning booths and sunlamps. Use sunscreen and wear protective clothing when outdoors. Tell your doctor right away if you get sunburned or have skin blisters/redness, or notice new or changed moles/skin lesions.

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).

Children may be at greater risk for liver problems and being more sensitive to the sun while using this drug (see above).

Tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant while using voriconazole. Voriconazole may harm an unborn baby. Ask about reliable forms of birth control while using this medication. If you become pregnant, talk to your doctor right away about the risks and benefits of this medication.

It is unknown if this medication passes into breast milk. Because of the possible risk to the infant, breastfeeding is not recommended while using this medication. Consult your doctor before breastfeeding.

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.

Voriconazole can slow down the removal of other medications from your body, which may affect how they work. Examples of affected drugs include eletriptan, ergot alkaloids (such as dihydroergotamine, ergotamine), certain drugs to treat irregular heartbeat (such disopyramide, dronedarone, quinidine), ivabradine, lurasidone, naloxegol, pimozide, ranolazine, sirolimus, certain "statin" cholesterol drugs (such as lovastatin, simvastatin), tolvaptan, among others.

Other medications can affect the removal of voriconazole from your body, which may affect how voriconazole works. Examples include butalbital, efavirenz, mitotane, rifamycins (such as rifabutin, rifampin), ritonavir, secobarbital, certain drugs used to treat seizures (such as carbamazepine, phenobarbital), St. John's wort, among others.

Many drugs besides voriconazole may affect the heart rhythm (QT prolongation), including pacritinib, among others.

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 1-800-222-1222. Canada residents can call 1-844-764-7669.

Lab and/or medical tests (such as liver/kidney function, blood mineral levels) 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.

It is important to get each dose of this medication as scheduled. If you miss a dose, ask your doctor or pharmacist right away for a new dosing schedule. Do not double the dose to catch up.

Consult the product instructions and your pharmacist for storage details. 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.