Itraconazole Risks, Warnings, and Complications

Precautions Before Starting Itraconazole

Tell your doctor if you have had allergic reactions to itraconazole oral, any of the active or inactive ingredients in itraconazole formulations, other antifungal agents, or any other drugs. Your pharmacy can give you a list of ingredients. Examples of other antifungal agents include fluconazole (Diflucan), ketoconazole (Nizoral, Extina, Recorlev), voriconazole (Vfend), posaconazole (Noxafil), and isavuconazonium (Cresemba). 

Give your doctor or pharmacist a complete list of your current medications, including prescription drugs, nonprescription drugs, vitamins, supplements, and herbal remedies. Also, tell your doctor or pharmacist about any medications you took within the last 14 days. This can help avoid possible interactions between itraconazole and your other medicines.

Give your doctor a complete medical history. Itraconazole may not be right for people with certain health conditions, such as cystic fibrosis, conditions that affect stomach acid production, low levels of white blood cells, organ transplants, a weak immune system, for example, HIV-infected patients or those living with acquired immunodeficiency syndrome (AIDS), or renal or hepatic impairment (kidney disease or liver disease).

Itraconazole may harm an unborn baby. Do not take this medicine if you are pregnant, could be pregnant, or are planning a pregnancy in the near future. Also, do not take it if you are breast feeding. Your doctor will ask you to start itraconazole 2-3 days after you get your menstrual period so that you know for sure that you are not pregnant. You should use effective birth control during the treatment and for at least 2 months after finishing treatment with this medication.

Precautions During Use of Itraconazole

Keep all your medical and lab appointments while on itraconazole oral. Continue taking the same dose of medication as prescribed, even if you feel well. Tell your doctor if your symptoms do not improve. Do not change the dose, dosage frequency, duration of treatment, or formulation (capsules or oral solution) without your doctor’s approval.

Make sure you administer acid-neutralizing medicines at least 1 hour prior or 2 hours after your itraconazole dose.

Itraconazole can cause blurred vision and double vision. Avoid driving, operating machinery, or participating in any hazardous activities until you know how this medicine affects you. 

Tell your doctor immediately if you become pregnant while on itraconazole.

Itraconazole Drug Interactions

Concomitant administration of itraconazole and certain other medicines can affect how the medicines work. Possible interactions between itraconazole and other medicines can increase the risk of serious adverse events. Your doctor may change the dose of your medications, switch you to another medication, or monitor you carefully for side effects if there are known interactions between itraconazole and your other medicines. 

Itraconazole can have drug interactions with the following medications:

• Acid-neutralizing medicines (H2 blockers) such as cimetidine (Tagamet HB), famotidine (Pepcid AC), nizatidine (Axid AR), and ranitidine
• Proton pump inhibitors such as lansoprazole (Prevacid 24HR), esomeprazole (Nexium 24HR), and omeprazole (Prilosec OTC, Zegerid OTC) 
• Fluticasone nasal spray (Flonase, Xhance, in Dymista)

You should not take itraconazole and the following medications together:

• Opioid pain medications such as methadone
• Medications used to treat irregular heartbeat, such as disopyramide, dofetilide, dronedarone, and quinidine
• Other antifungal medicines such as isavuconazole
• Ergot alkaloids such as ergotamine, dihydroergotamine, methylergometrine (methylergonovine), and ergometrine (ergonovine)
• Cancer treatment drugs such as irinotecan
• Medications used to treat psychiatric disorders, such as lurasidone
• Benzodiazepines (anti-anxiety medications) such as triazolam
• Oral midazolam (used before surgical procedures to reduce anxiety)
• Medications prescribed to control tics, such as pimozide
• Blood pressure medicines such as felodipine and nisoldipine (calcium channel blockers)
• Medications prescribed for congestive heart failure, such as ivabradine and eplerenone
• Medications prescribed for angina (chest pain), such as ranolazine
• Heartburn and GERD medications such as cisapride
• Medications used to treat constipation caused by opioid medications, for example, naloxegol
• Cholesterol-lowering medicines like lomitapide, simvastatin, and lovastatin
• Erectile dysfunction medications like avanafil
• Antiplatelet drugs like ticagrelor

You should not take the following medications with itraconazole if you have renal or hepatic impairment:

• Gout medications such as colchicine
• Medications prescribed for bladder control, such as fesoterodine 
• Medications for overactive bladder, such as solifenacin

You should not take eliglustat for Gaucher’s disease if you are a poor or intermediate metabolizer of CYP2D6 enzyme or take strong or moderate CYP2D6 inhibitors. 

You should not take itraconazole during the dose initiation or ramp-up phase of venetoclax for chronic lymphocytic leukemia or small lymphocytic lymphoma (SLL).

Give your health care professional a complete list of all the medications you are taking, including prescription drugs, non-prescription medicines, dietary supplements, and herbal remedies. Tell your doctor about any medications you took in the last two weeks. Do not start taking any over-the-counter medications while on itraconazole without checking with your doctor first. Also, tell your healthcare provider if you smoke, drink alcohol, or use recreational drugs because some of these substances can cause serious health complications when used with prescription and over-the-counter medicines.