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Fulvicin-U/F (Oral)

Generic name: griseofulvin

Brand names: Fulvicin P/G, Fulvicin-U/F, Grifulvin V, Gris-PEG

Last updated November 12, 2025 0 views
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Uses for Fulvicin-U/F

Griseofulvin is an antifungal medicine. It is used to treat fungal infections of the body, feet, groin and thighs, scalp, skin, fingernails, and toenails. You can take this medicine by itself or with other medicines that are applied to the skin for fungal infections.

It has not been proven effective for preventing fungal infections.

This medicine is available only with a prescription from your doctor.

This section was rewritten for readability and reviewed for meaning.

Precautions while using Fulvicin-U/F

It is very important for your doctor to check how you or your child is doing at regular visits to ensure that this medicine is working well and to look for any unwanted effects.

If your symptoms do not get better, or if they worsen, talk to your doctor. You may need to take this medicine for several weeks or months before your infection improves.

Using this medicine while you are pregnant may cause serious unwanted effects in your newborn baby. Tell your doctor immediately if you think you are pregnant or plan to become pregnant while using this medicine.

Serious skin reactions can happen with this medicine. Stop using it and contact your doctor right away if you or your child experience blistering, peeling, or loosening of the skin; red skin lesions; severe acne or skin rash; sores or ulcers on the skin; or fever or chills while using this medicine.

Stop using this medicine and contact your doctor immediately if you or your child have pain or tenderness in the upper stomach; pale stools; dark urine; loss of appetite; nausea; unusual tiredness or weakness; or yellow eyes or skin. These could be signs of a serious liver problem.

Griseofulvin has been shown to cause liver and thyroid tumors in some animals. You and your doctor should discuss the benefits of this medicine and the risks of taking it.

Birth control pills containing estrogen may not work properly if you take them while using griseofulvin. Unplanned pregnancies may happen. To avoid getting pregnant, use another form of birth control for up to 1 month after your last treatment. Other birth control methods include condoms, diaphragms, or contraceptive foams or jellies.

Griseofulvin may enhance the effects of alcohol. If taken with alcohol, it may also lead to fast heartbeat, flushing, increased sweating, or redness of the face. If you experience these symptoms, do not drink alcohol while taking this medicine unless you have checked with your doctor first.

This medicine may cause some people to feel dizzy, drowsy, or less alert than usual. Make sure you know how this medicine affects you before you drive, operate machinery, or do other activities that could be dangerous if you are dizzy or not alert. If these effects are particularly bothersome, consult your doctor.

Griseofulvin may make your skin more sensitive to sunlight than usual. Even brief exposure to sunlight may lead to a skin rash, itching, redness or other discoloration of the skin, or severe sunburn. When you start taking this medicine:

  • Avoid direct sunlight, especially between 10:00 a.m. and 3:00 p.m., if possible.
  • Wear protective clothing, including a hat, and sunglasses.
  • Use a sunblock product with a skin protection factor (SPF) of at least 15. Some patients may need a product with a higher SPF, especially if they have fair skin. If you have questions about this, ask your doctor.
  • Use a sunblock lipstick with an SPF of at least 15 to protect your lips.
  • Do not use a sunlamp or tanning bed or booth.

If you have a severe reaction to the sun, consult your doctor.

Do not take other medicines unless you have discussed them with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

This section was rewritten for readability and reviewed for meaning.

Before using Fulvicin-U/F

In deciding to use a medicine, you and your doctor need to weigh the risks of taking the medicine against the benefits it may provide. Consider the following for this medicine:

Allergies

Inform your doctor if you have ever had any unusual or allergic reactions to this medicine or any other medicines. Also, let your healthcare professional know if you have other allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, carefully read the label or package ingredients.

Pediatric

Studies so far have not shown any specific problems that would limit the use of griseofulvin in children. However, safety and effectiveness have not been established in children up to 2 years of age.

Geriatric

There is no information available about how age affects the effects of griseofulvin in older patients.

Breast Feeding

There are no adequate studies in women to determine the risk to infants when using this medication while breastfeeding. Consider the potential benefits against the risks before using this medication during breastfeeding.

Interactions with Medicines

Some medicines should not be used together at all, while in other cases, two different medicines may be used together even if an interaction could happen. In such cases, your doctor may adjust the dose or take other precautions. It is especially important for your healthcare professional to know if you are taking any of the medicines listed below while using this medicine. The following interactions have been highlighted for their potential significance, but this list may not include all interactions.

Using this medicine with any of the following medicines is usually not recommended but may be necessary in some situations. If both medicines are prescribed together, your doctor may change the dose or frequency of one or both medicines.

  • Desogestrel
  • Dienogest
  • Drospirenone
  • Estradiol
  • Ethinyl Estradiol
  • Ethynodiol
  • Etonogestrel
  • Gestodene
  • Levoketoconazole
  • Levonorgestrel
  • Medroxyprogesterone
  • Mestranol
  • Methotrexate
  • Nomegestrol
  • Norelgestromin
  • Norethindrone
  • Norgestimate
  • Norgestrel
  • Porfimer
  • Segesterone
  • Ulipristal

Using this medicine with any of the following medicines may increase the risk of certain side effects, but using both medicines may be necessary for your treatment. If both medicines are prescribed together, your doctor may adjust the dose or frequency of one or both medicines.

  • Aminolevulinic Acid
  • Phenobarbital
  • Warfarin

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be taken around the time of eating food or specific types of food due to potential interactions. Using alcohol or tobacco with certain medicines may also lead to interactions. The following interactions have been chosen for their potential significance and may not include all possibilities.

Using this medicine with any of the following is usually not recommended but may be unavoidable in some cases. If used together, your doctor may adjust the dose or frequency of this medicine or provide special instructions regarding food, alcohol, or tobacco use.

  • Ethanol

Other Medical Problems

Having other medical problems may affect the use of this medicine. Be sure to tell your doctor if you have any other medical conditions, especially:

  • Actinomycosis (bacterial infection) or
  • Blastomycosis (Gilchrist’s disease) or
  • Candidiasis (yeast infection) or
  • Histoplasmosis (Darling’s disease) or
  • Other infections (e.g., bacteria) or
  • Sporotrichosis (Rose gardener's disease) or
  • Tinea versicolor (Tinea flava)—Griseofulvin will not be effective in patients with these conditions.
  • Liver failure or
  • Porphyria (enzyme problem)—Should not be used in patients with these conditions.
  • Lupus erythematosus or lupus-like diseases—Use with caution, as it may worsen this condition.

This section was rewritten for readability and reviewed for meaning.

Side Effects of Fulvicin-U/F

Along with its necessary effects, a medicine can cause some unwanted effects. Not all of these side effects may happen, but if they do, they may require medical attention.

Contact your doctor right away if any of the following side effects occur:

More common

  • Blistering, peeling, or loosening of the skin
  • chills
  • cough
  • diarrhea
  • fever
  • itching
  • joint or muscle pain
  • red, irritated eyes
  • sore throat
  • sores, ulcers, or white spots in the mouth or on the lips
  • unusual tiredness or weakness

Less common

  • Confusion
  • increased sensitivity of the skin to sunlight
  • skin rash, hives, or itching
  • soreness or irritation of the mouth or tongue

Rare

  • Black, tarry stools
  • chest pain
  • cloudy urine
  • large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
  • numbness, tingling, pain, or weakness in the hands or feet
  • painful or difficult urination
  • shortness of breath
  • swollen glands
  • unusual bleeding or bruising
  • yellow eyes or skin

Incidence not known

  • Abdominal or stomach pain
  • burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • clay-colored stools
  • dark urine
  • dizziness
  • headache
  • loss of appetite
  • nausea
  • unpleasant breath odor
  • vomiting of blood

Some side effects may occur that usually do not need medical attention. These side effects may go away as your body gets used to the medicine. Also, your health care professional may be able to provide ways to prevent or lessen some of these side effects. Contact your health care professional if any of the following side effects continue or are bothersome, or if you have any questions about them:

More common

  • Hives or welts
  • redness of the skin

Less common

  • Trouble with sleeping

Incidence not known

  • Heartburn
  • pain or discomfort in the chest, upper stomach, or throat
  • sleeplessness
  • unable to sleep
  • white patches in the mouth or throat or on the tongue
  • white patches with diaper rash

Other side effects not listed may also occur in some patients. If you notice any other effects, contact your healthcare professional.

Call your doctor for medical advice about side effects. You can report side effects to the FDA at 1-800-FDA-1088.

In the U.S.

  • Fulvicin P/G
  • Fulvicin-U/F
  • Grifulvin V
  • Gris-PEG

Available Dosage Forms:

  • Tablet
  • Suspension

Therapeutic Class: Antifungal

This section was rewritten for readability and reviewed for meaning.

Proper use of Fulvicin-U/F

Keep using this medicine for the full treatment time, even if you feel better after the first few doses. Your infection may not clear up if you stop using the medicine too soon.

Keep yourself clean to help control infection and prevent reinfection.

Griseofulvin is absorbed best when it is taken with a high fat meal, such as a cheeseburger, whole milk, or ice cream. Tell your doctor if you are on a low-fat diet.

Griseofulvin is best taken with or after meals, especially fatty ones (e.g., whole milk or ice cream). This lessens possible stomach upset and helps to clear up the infection by helping your body absorb the medicine better. However, if you are on a low-fat diet, check with your doctor.

For patients taking the oral liquid:

  • Use a specially marked measuring spoon or other device to measure each dose accurately. The average household teaspoon may not hold the right amount of liquid.

You may swallow the tablets whole or sprinkle the crushed tablets in one tablespoonful of applesauce. Swallow it immediately without chewing.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage forms (microsize capsules, tablets, or suspension): Treatment of fungus infections of the feet and nails: Adults and teenagers—500 milligrams (mg) every 12 hours. Children—Dose is based on body weight and must be determined by your doctor. The usual dose is 5 milligrams (mg) per kilogram (kg) (2.3 mg per pound) of body weight every 12 hours, or 10 milligrams (mg) per kilogram (kg) (4.6 mg per pound) of body weight once a day. Treatment of fungus infections of the scalp, skin, and groin: Adults and teenagers—250 milligrams (mg) every 12 hours or 500 mg once a day. Children—Dose is based on body weight and must be determined by your doctor. The usual dose is 5 milligrams (mg) per kilogram (kg) (2.3 mg per pound) of body weight every 12 hours, or 10 milligrams (mg) per kilogram (kg) (4.6 mg per pound) of body weight once a day.
  • For oral dosage form (ultramicrosize tablets): Treatment of fungus infections: Adults—375 milligrams (mg) per day, taken as a single dose or divided in small doses. Some patients may need 750 mg divided in small doses. Children 3 years of age and older weighing over 60 pounds—Dose is based on body weight and must be determined by your doctor. The usual dose is 187.5 to 375 mg per day. Children 3 years of age and older weighing 35 to 60 pounds—Dose is based on body weight and must be determined by your doctor. The usual dose is 125 to 187.5 mg per day. Children up to 2 years of age—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Related medicines

Before you take this medicine: the information on this page is general and may not cover your personal circumstances. Read the label supplied with your medicine and ask a pharmacist or doctor if you are unsure, especially if you are pregnant, breastfeeding, taking other medicines or managing a long-term condition.
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