Interacting drugs- summary

Griseofluvin + Anticoagulants decr griseofluvin decrease the hypoprothrombinemic activity of warfarin, patients require anticoagulant dosage adjustment

Oral Contraceptives-                                                                                                              loss of contraceptive effectiveness occur, possibly leading to breakthrough bleeding, amenorrhea or unintended pregnancy

Cyclosporine-                                                                                                                  cyclosporine levels reduced, resulting in a decrease in pharmacologic effects

Salicylates-                                                                                                                      serum salicylate concention decreased

+ Griseofulvin

Barbiturates decr serum griseofluvin levels decreased 

Ringworm infections of skin, nails, hair, tinea infections.

Most common- Hypersensitivity reactions, such as skin rashes, urticaria, and rarely angioneurotic edema may occur. Occassional Oral thrush, nausea, vomiting, epigastric distress, diarrhea, headache, fatigue, diziness, insomnia, mental confusion,impairment of performance of routine activities.

Rare- Griseofluvin interferes with porphyrin metabloism. Proteinuria,leukopenia, hepatic toxicity, GI bleeding, menstrual irregularities, parasthesis of the hands and feet after extended therapy. Discontinue administration if granulocytopenia occurs. When rare, serious reactions occur with griseofluvin, they are usually associated with high dosages long periods of therapy or both

Severe liver disease.

Pregnancy, porphyria. Monial infection, SLE.

Special precautions:

Concurrent administration of coumarin, barbiturates or oral contraceptives Do not use prophylactically Monitor LFTs. Neonates.

Lactation:

Prolonged therapy- closely observe patients on prolonged therapy. Periodically monitor renal, hepatic, and hemopoietic function.

Penicillin- cross sensitivity- is possible because griseofluvin is derived from species of penicillin Penicillium- however known penicillin-sensitive patients have been treated without difficulty.

Lupus erythematosus- lupus like syndrome or exacerbation of lupus erythematos have occured in patients receiving griseofluvin

Photosensitivity- may occur, caution patients to take protective measures (eg sunscreens, protective clothing), against exposure to ultraviolet light or sunlight. Photosensitivity reactions may aggrevate lupus erythematosus.

Warnings-

Prophylaxis- safety and efficacy for prophylaxis of fungal infections have not been established

Hypersensitivity reactions- (eg skin rashes, urticaria, angioneurotic edema) may occur and necessitate withdrawal of therapy.

Carconogenisis- Griseofluvin produced disturbances in porphyrin metabolism,a colchicine-like effect on mitosis and cocarcinogenicity with methylcholantrene in cutaneous tumor induction in laboratary animals.

Pregnancy- Do not give to pregnant or women contemplating pregnancy.

Indications:

Ringworm infections of skin, nails, hair, tinea infections.

Dosage:

Adults- a single or divided daily dose of 500mg.. Children- 11mg microsize/kg/day.

Missed dose

1. If you miss a dose of this medicine, take it as soon as possible.

2. However, if it is almost time for next dose, skip the missed dose and go back to your regular dosing schedule.

3. Do not double doses.

1. Beneficial effects may not be noticeble for some time; continue taking medication for entire course of therapy

2.Photosenitivity reactions may occur; avoid prolonged exposure to sunlight or sun lamps.

3. Notify physician if fever, sore throat or skin rash occurs.

4.Allergies- tell your doctor if you have ever had any unusual or allergic reaction to penicillins, penicillamine or griseofluvin. Also tell your doctor if youare allergic to any other substances, such as foods, presrvatives or dyes.

5.Diet- griseofluvin is absorbed best when it is taken with a high fat mweal, such as cheeseburger, whole milk or ice cream. Tell your doctor if you are on alow fat diet.

6.Pregnancy - should not be used during pregnancy.

7.Breast feeding- griseofluvin has not been reported to cause problems in nursing babies

8 Children - medicine has not been been shown to cause different side effects or problems than it does in adults.

9. Elderly- this medicine is not expected to cause different side effects or problems in older people than it does in younger adults.

10. Other medicines - Let your doctor know what other medicines you are taking, so that he can advice you accordingly. Anticoagulants - may increase the effect of the anticoagulants in some patients Oral contraceptives - grisefluvin may decrease the effectiveness of birth control pills , which may result in breathrough bleeding and unwanted pregnancies

11. Other medical problems - Tell your doctor if you have any other medical problems especially - Liver disease - griseofluvin may on rare occassions cause side effects affecting the liver Lupus erythematous - grisefluvin may worsen lupus symptoms in patients who have lupus erthematous disease or lupus like disease Porphyria- griseofluvin may increase attacks of porphyria in patients with acute intermittent porphyria,

12. Missed dose - If you miss a dose of this medicine, take it as soon as possible. however, if it is almost time for the next dose, skip the missed dose. Do not double doses.

13. Storage - Keep out of reach of children. Store away from heat or direct sunlight. Do not store the capsule in bathroom, near the kitchen sink, or in other damp places.

14. Outdated medicines - Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of reach of children.

Pharmacology:

Griseofulvin an antibiotic derived from a species of Penicillium, is deposited in keratin precursor cells which are gradually exfoliated and replaced by noninfected tissue.

Pharmacokinetics:

Peak serum level occurs at about 4 hours and ranges betwen 0.5 to 2mcg/ml.

Highly fatty diet increases bioavailbility.

Pregnancy

Do not give to pregnant women or women cotemplating pregnancy