Uses, Side Effects and Prescription of Fluconazole

Overview

Fluconazole is a member of the triazole family, one of the most widely used antifungal agents. Its common name is Diflucan. Fluconazole was patented in 1981, and commercial usage was started in 1988. It is listed in the World Health Organization’s List of Essential Medicines. Fluconazole is available as a generic medication. In 2020, fluconazole was one of the most prescribed drugs, with over three million prescriptions.

It is an antifungal drug that works by slowing fungi growth, which is a reason for infection. Use of Fluconazole for the treatment of both systemic and superficial fungal infections in a variety of tissues. This drug is an azole antifungal in the same family as ketoconazole and itraconazole. Fluconazole has many advantages over other antifungal drugs, including the option of oral administration. Furthermore, the side effect profile of this drug is minimal. It has been an efficacious treatment for vaginal yeast infections in one dose.

This article will focus on Fluconazole uses, its side effects, and all precautions you should take.

How to take fluconazole?

Please do not take it often, and do not take it for longer. Doing so may increase the possibility of side effects. Read and follow the instructions carefully that come with a patient information leaflet.

If it helps improve the condition after the first few doses of this drug, use this medicine for complete treatment. If you stop using the drugs too soon, your infection may not clear. You can take this medicine with or without food. Shake the oral liquid well before use every time. If you are taking the liquid composition of this medicine, then measure with a measuring spoon, medicine cup, or oral syringe. The household teaspoon may not hold the right amount of liquid. Take this drug by mouth with or without food once a day. 

The fluconazole dosage depends on your medical condition and response to treatment. For children, dosing is based on weight. Generally, for children, the dose should not exceed 600 milligrams per day unless directed by a doctor. Fluconazole works best when the amount of medicine in your body is maintained at a constant level. 

The course of medication should be complete, even if symptoms disappear after a few days. Stopping the medicine too early may allow the fungus to grow, which may result in the infection returning.

Most adults and children can take fluconazole. It is also a prescription medicine for babies.

Who Should Not Take Fluconazole?

 Fluconazole is not suitable for people having the following issues:-

• Heart disease, including heart rhythm problems (arrhythmia)
• Kidney or liver issues
• Allergic reaction to fluconazole or any other drugs in the past
• Had a blood test that showed abnormal levels of potassium, calcium, or magnesium
• An inherited blood disorder called acute porphyria

Capsule form of fluconazole is available in 50mg, 150mg, or 200mg. Swallow the whole tablet with water. The liquid form usually comes in two different forms:

• 50mg/5ml. 50mg fluconazole in a 5ml spoonful 
• 200mg/5ml. 200mg fluconazole in a 5ml spoonful

Dosage for capsules or liquid

The following are the usual doses for adults:-

• Weak immune system:  (a low white blood cell count). Take 50mg to 400mg a day until your white blood cell count improves.
• Candida infections: Use 200mg to 800mg a day for several weeks.
• Oral (mouth) thrush: Take 50mg daily for 7 to 14 days.
• Vaginal thrush or balanitis: Use 150mg as a single dose.
• Vaginal thrush that keeps coming back: Take 150mg once every 72 hours for the first three doses, then take 150mg once weekly for six months.
• Cryptococcal meningitis: Take 200mg to 800mg a day for several weeks.
• To stop cryptococcal meningitis from returning: Use 200mg daily for the term.

Note: If you take fluconazole once every 72 hours, use a calendar and mark the days you need to take it.

How does fluconazole work?

Fluconazole (Diflucan) is an antifungal medication. It works by slowing the growth of the fungus causing your infection. It inhibits a fungal enzyme called lanosterol 14-α-demethylase, which normally converts lanosterol (a fat) into ergosterol, thereby interfering with the formation of the fungal cell membrane.

Diseases you can treat with fluconazole

The following are the treatment which these medicines can provide:-

• Effective against Cryptococcus neoformans, Candida albicans, C. glabrata, C. parapsilosis, C. tropicalis, and several other Candida species.
• A single oral dose is usually sufficient to treat vaginal candidiasis.
• The fluconazole dose for skin infection can treat certain fungal or yeast infections.
• To treat vaginal candidiasis.
• Effective for other Candida infections, such as those of the urinary tract, esophagus, and mouth, as well as peritonitis and systemic infections
• To reduce the chances of candidiasis in people receiving chemotherapy, radiotherapy, or undergoing bone marrow transplantation.
• To treat Cryptococcal meningitis in AIDS patients.

Have you caught one of the above Fungal infections? Please consult one of our healthcare providers at Your Doctors Online for prompt diagnosis and treatment.

How long does it take for fluconazole to work?

It depends on the fungal condition. If you are suffering from vaginal yeast infection, you may only need one dose of fluconazole and may see your symptoms start to improve within 24 hours.

For some other infections (like oral thrush), it may take several days before you start to feel better. It could take longer for more severe conditions, like blood or liver infections. 

Even if you start feeling better, you should continue taking fluconazole until your course is complete. Stopping fluconazole too soon can prevent your infection from being fully treated. An incomplete approach can cause disease symptoms to return.

Usually, a single-dose prescription for mild, uncomplicated infections will improve symptoms within 1 to 3 days.

Also, if a single dose does not completely relieve symptoms or the infection is severe, fluconazole can be given as three consecutive doses, three days apart. This practice may improve symptoms within one to two weeks.

If symptoms continue despite suitable treatment, fluconazole may be recommended for everyday use for ten to fourteen days and even once weekly for six months.

In case of an emergency or overdose

If you have taken too many doses accidentally, you could have deadly drug levels in your body. 

Symptoms of an overdose of this drug include:-

• Hallucinations
• Paranoia
• Abnormal heart rhythm
• Blue tint to your skin
• Decreased breathing

Acute toxicity of fluconazole can present with peripheral nervous system involvement. In addition, the patient developed polyneuropathy, a confusional state, acute kidney injury, and thrombotic thrombocytopenic purpura. Reports exist of fluconazole overdose accompanied by hallucinations and paranoid behavior. Moreover, symptomatic treatment with supportive measures and gastric lavage should be instituted if there is an overdose. As fluconazole is excreted in urine, a 3-hour hemodialysis session decreases plasma levels by approximately 50%.

Get help immediately by consulting one of our doctors online if any overdose symptoms occur.

What should you do if you forget a dose?

If you need to remember to take a dose:

1. Please take it as soon as you remember, unless it’s time for your next dose.
2. In this case, skip the missed dose and take your next dose as usual.
3. Take a double amount to cater for a missed dose. If you often forget doses, set an alarm to remind you. 

Precautions you should follow.

Before taking fluconazole

• Inform your doctor if you are allergic to fluconazole or to other antifungal medications such as posaconazole (Noxafil), voriconazole (Vfend), itraconazole (Sporanox), ketoconazole (Nizoral), or any of the ingredients in fluconazole tablets.
• Take advice from your doctor if you are taking astemizole (Hismanal) (not available in the U.S.), cisapride (Propulsid) (not available in the U.S.), quinidine (Quinidex), erythromycin (E.E.S., E-Mycin, Erythrocin); pimozide (Orap) or terfenadine (Seldane). Your doctor will advise you not to take fluconazole if you take any of these medications.
• Explain to your doctor what prescription and nonprescription vitamins, medications, nutritional supplements, and herbal products you plan to take. 
• Communicate with your doctor if you have or have ever had cancer, an irregular heartbeat, or acquired immunodeficiency syndrome (AIDS)
• Inform your doctor if you are pregnant, especially if you plan to become pregnant, are in the first three months, or are breastfeeding. Your doctor can advise you to use birth control to prevent pregnancy while using medicines.
• If you have dental surgery or any other surgery, inform your dentist or doctor that you are using fluconazole.
• As fluconazole may make you dizzy or cause seizures, do not operate machinery or drive a car until you know how this drug can affect you.

Side effects of fluconazole

Immune-compromised or HIV/AIDS patients are likely to have fluconazole side effects. Fluconazole’s side effects, such as nausea, headache, and stomach pain, can start quickly if given an injection. But minor side effects could occur within an hour or two when taking fluconazole by mouth.

Common side effects

• Headache. It is the most common side effect in people receiving a large dose.
• Nausea. It is the most common side effect in people taking multiple smaller doses.
• Abdominal pain. This is a common side effect of fluconazole, which is more likely when administering the drug in a single large dose. In clinical trials, about 6% of people receiving a single large dose reported stomach pain.

Other common side effects may include

• Vomiting
• Diarrhea
• Acid indigestion
• Dizziness
• Changes in how things taste
• Skin rash. This is an uncommon side effect of fluconazole and mainly happens in people taking fluconazole for several days. A skin rash may not be a medical emergency, but it could be an early sign of a severe, sometimes even life-threatening, skin reaction to the drug. 

Serious side effects of fluconazole

The most severe side effects of fluconazole include the following:

• Liver problems
• Seizures
• Decreased white blood cell or platelet counts
• Heart rhythm changes
• Decreased adrenal gland function
• Severe allergic or skin reactions

Storage and disposal of Fluconazole

For storage and disposal purposes, always follow the under-mentioned points:

• Keep this medication in the container in which it came.
• Do not keep outdated or unused medicine.
• Keep out of reach of children. It is essential to keep all medication out of reach of children. Many containers are not child-resistant, and they can open easily. Therefore, always lock safety caps and keep the medicine in a safe location. 
• Store it at room temperature.
• Keep away from excess heat and moisture. 
• Dispose of unused liquid medication after 14 days.
• Unneeded medications should be disposed of properly to ensure that children, pets, and others cannot consume them. 
• Never flush this medication down the toilet.
• The most appropriate way to dispose of your medication is through a medicine take-back program.

Sign up on Your Doctors Online to learn about take-back programs in your community.

How to reduce its side effects?

Most people will experience mild or no side effects while taking fluconazole. If they have, then they’re usually manageable. Here are some practical ways to minimize and reduce the possibility:

Follow the instructions

Follow all instructions given by the prescriber or written on the prescription label while taking fluconazole. Only take what is instructed. 

Rest assured, the prescriber has a complete medical history.

Medical status may affect whether fluconazole causes problems, so make sure the prescriber is well aware of these conditions, mainly:

• Heart rhythm problems
• Low potassium or other electrolyte imbalances
• Liver problems
• Heart disease
• Kidney problems
• Pregnancy or pregnancy plans
• Breastfeeding or breastfeeding plans

Make sure the prescriber is well aware of all medications. 

The prescriber needs to know the prescription drugs, vitamins, over-the-counter medications, or dietary supplements being taken.

Take fluconazole with food.

Use Fluconazole pills or fluconazole oral solutions with or without food. If nausea is a problem, take each dose with a snack or meal.

Avoid pain relievers

Fluconazole may increase side effects like stomach pain caused by NSAIDs like naproxen and ibuprofen. However, this is not dangerous; use acetaminophen for pain or fever.

How to treat the side effects of fluconazole

The following are the ways to manage side effects:-

Headache

• Fluconazole and alcohol have an interaction. Don’t t drink too much alcohol. 
• Take an over-the-counter pain reliever like acetaminophen.
• Drink fluids and rest in a cool, dark, quiet room. 

Liver problems

Fluconazole can cause dangerous liver problems, so contact a doctor if any symptoms of liver dysfunction are noticed, such as:

• Foul-smelling or dark urine
• Pale/clay-colored stools
• Vomiting
• Tiredness
• Loss of appetite
• Whites of the eyes
• Yellowing of the skin  

Stomach pain

• Try to rest and relax. 
• Eat and drink slowly
• and have smaller and more frequent meals. 
• Put a heating pad or a covered hot water bottle on your tummy
• If you are in severe pain, talk to our doctor 

Diarrhea

• Drink lots of fluids to avoid dehydration. 
• Do not take other medicines to treat diarrhea without speaking to a pharmacist or doctor.

Feeling or being sick (nausea or vomiting)

• Have simple meals and avoid rich or spicy food. 
• Have small sips of water to avoid dehydration.

Factors that increase the risk of a reaction

While rare, severe, life-threatening allergic or skin reactions may occur. Patients taking fluconazole should be alert to signs of an allergic reaction, like difficulty breathing, hives, swelling of the tongue, face, lips, or throat. 

Patients should also be alert to symptoms of a severe skin reaction, such as fever, burning eyes, sore throat, red or purple rash, or blistering or peeling skin. Also, emergency medical attention is required for patients experiencing an allergic or skin reaction. 

Discuss your risk factors for a reaction with one of our doctors online.

How long do side effects last?

Fluconazole is a short-term, time-limited treatment. It can be given as a single large or multiple daily doses for one to three weeks. Most people can expect side effects to resolve when treatment stops. However, it takes some time for the body to clear a dose. Healthy people clear fluconazole in about five days, but it may take two to three weeks in people with kidney disease. Severe but rare adverse effects, such as low white blood cell counts or adrenal insufficiency, may take several weeks to recover from.

Drug interaction

Fluconazole is an antifungal medication. It’s an option for many situations, such as a yeast infection. But many fluconazole interactions can be harmful if left unchecked. 

Fluconazole is known to interact with many other medications. Some of which you may be taking. Sharing the details of medicines with your doctor is helpful before you start your new prescription. This helps them prevent and check for any possible medication interactions.

Warfarin

It is a blood-thinning medication. It treats and prevents blood clots. This helps stop certain complications for people with atrial fibrillation and strokes. However, after taking warfarin, it is broken down by two specific enzymes. Fluconazole prevents these enzymes from working efficiently. So if you take warfarin and fluconazole simultaneously, the INR can increase. It leads to blood thinning, which can be dangerous if not managed.  

Your doctor may want to lower your warfarin dose if you are to take fluconazole simultaneously. You will be required to investigate INR often because an elevated INR can raise your risk of bleeding. 

Amiodarone (Pacerone)

It is a drug that is used in the treatment of abnormal heart rhythms. Fluconazole can also lead to changes in heart rhythm, albeit unintentionally. There’s an elevated risk of developing irregular heart rhythms when taken together. Fluconazole also makes amiodarone stick around the body longer, prolonging its efficacy.

Your doctor may want to monitor your heart rhythm more often while you are taking both medications. Additionally, they may want to ensure that your body’s potassium and magnesium levels are within normal ranges. This can help prevent heart problems. 

Clopidogrel (Plavix)

Clopidogrel is a frequently used antiplatelet medication. It’s a medicine to lower the risk of heart attack and stroke prescribed to certain patients.

However, clopidogrel does not start to work right away. It works only after enzymatic activation. Fluconazole can stop this enzyme from working, making it ineffective and can worsen and increase the risk of cardiac complications.

Also, if you are on clopidogrel, it may be a good idea to check in with our doctors to see if any dose adjustments or other changes are necessary. 

Phenytoin (Dilantin)

It is a medicine to help prevent seizures in people with epilepsy. Normally, phenytoin gets excreted from your body by an enzyme. Fluconazole can hinder this. It may lead to serious phenytoin side effects because it stays in your body longer. Additionally, it can contribute to cardiac side effects, like hypotension or heart rhythm abnormalities. Brain-related side effects can also occur, like slurred speech, drowsiness, and dizziness.

If you take phenytoin, your doctor may want to track your phenytoin levels more often while on fluconazole. Your healthcare provider may also lower your phenytoin dose. 

Atorvastatin (Lipitor)

It is a typical high-cholesterol medication that benefits several health conditions, like heart disease and diabetes, but interactions are a frequent concern.

 Atorvastatin is removed from the body by a specific enzyme, but fluconazole may inhibit that enzyme. It can increase atorvastatin levels in the body. 

In addition, elevated atorvastatin levels can lead to more side effects. These can include rhabdomyolysis or muscle pain, where your muscles break down and release harmful by-products.

Citalopram (Celexa)

It is an antidepressant drug used in the treatment of depression. It increases serotonin levels in your brain to help improve your mood. 

However, increased serotonin can be dangerous. Elevated serotonin could lead to serotonin syndrome, a severe health condition. It doesn’t typically cause serotonin syndrome alone, but the risk is higher while on fluconazole. Fluconazole slows down the two enzymes that usually break down citalopram. 

Serotonin syndrome’s severity varies. Moreover, mild symptoms include shaky hands, sweating, and an increased heart rate. But in rarer cases, more severe symptoms can occur.

 The following symptoms are the recommendation for Emergent medical care :

• Confusion
• Rapid eye movements
• An inability to open your mouth (lockjaw)
• Uncontrolled movement of arms and legs
• Difficulty in rising from a lying or sitting position

Additionally, some antidepressants can affect your heart and raise the risk of abnormal rhythms. As with amiodarone, taking citalopram and fluconazole can increase the risk of heart rhythm problems. This risk is higher for people who have preexisting heart problems. 

If you’re taking both citalopram and fluconazole together, citalopram’s labeling recommends limiting the dose to 20 mg once daily while taking fluconazole.

Fluconazole’s behavior can make some medications stick around in your body longer than needed. This increases the odds of side effects. On the other hand, blocking these enzymes can make other medicines less effective. So, if you took any drugs or supplements and were just given a prescription for fluconazole, these interactions are essential to know about.

Remember: This isn’t an exhaustive list of medications that interact with fluconazole. 

How to get a fluconazole prescription?

Worried that you may be having a fungal infection. Fluconazole may be the right choice for treatment, depending on the disease condition, patient age, weight, and overall medical condition. Some formulations may be available over the counter, but most require a prescription. Start an online prescription consultation to get Fluconazole delivered to your local pharmacy.

F.A.Q.s about Fluconazole Answered by Your Doctors Online Team