Griseofulvin - antimicrobial drug and its therapeutic uses

DESCRIPTION:   
Griseofulvin [trade name: Gris-peg and Grifulvin V] is an orally administered antifungal drug. It is used both in animals and humans, to treat fungal infections of the skin and nail fungus.
It was discovered in the culture broth of the certain species of the mold Penicillium in 1939.
It is on the World Health Organization’s List of Essential Medicine.
It is produced industrially by fermenting the the fungus Penicillium patulum.
This drug belongs to class of organic compounds known as bezofurans. These are organic compounds containing a benzene ring fused to a furan.

MECHANISM OF ACTION: 
 Griseofulvin is fungistatic, however the exact  mechanism by which it inhibits the growth of dermatophytes is not clear .It is through to inhibit fungual cell mitosis and nuclear acid synthsis. It also binds to the interferes with the function of spindle and cytoplsmic  microtubules by binding to alpha and beta tublin. It binds to keratin in humans cells, then once it reachs the fungal site of action, it binds to fungal microtubules thus altering the fungal process of mitosis.

PHARMACOLOGY:
Griseofulvin is a mycotic product of penicillnium spp. Griseofulvin is fungistatics with in vitro activity against  various speciesv of Microsporum Epidermophyton.
Absorption :  Poorly absorbed from GI ranging from 25 to 70% of an oral dose. Absorption  is  significantly enhanced by administration with or after a fatty meal.
Metabolism : Primarily hepatic with major metabolites being 6-methyl-griseofulvin and its glucuronide conjugate.
Half life :  9 – 21 hours.

 THERAPEUTIC USES:
Griseofulvin is used to treat infections such as ringworm, athlete’s foot, jock itch and fungal infection of the scalp , finger nails or toe nails.
Griseofulvin should not use ,if a person have porphyria or liver failure.
It should not use during the first  3 months of pregnancy may harm the unborn baby.

SIDE EFFECTS :
Common side effects may include :-
• Nausea
• Vomiting ( due to stimulation of the emetic centre , situated in the medulla oblongata)
• upset stomach ,
• Diarrhea (due to increase propulsive movement ,decreases the absorption)
• Headache, tired feeling
• Sleep problems (insomnia)
• Itching ,rash

Severe side effects:-
• Swelling of face or tounge
• Hives
• Fever
• Steven jhonson symdrome ( due to disorder of the immune system)
• Skin blister or peeling
• Jaundice ( due to higher amount of billirubin)
• Joint pain


DRUG-DRUG INTERACTION :
• Acenocoumarol + Griseofulvin = the serum concentration of Acenocounarol can be decreased ,when it is combined with Griseofulvin.

• Cyclosporine + Griseofulvin = the serum concentration of cyclosporine can be decreased ,when it is combined with griseofulvin.

• Alcohal + Griseofulvin = can cause unpleaseant.

• High fat meal, fatty + Griseofulvin = increase bioavailability.

REFERENCE :
Tripathi KD, Essential of Medical Pharmacology, 7th edition, Jaypee Brothers Medical Publisher (P) LTD. Page No: 790