Is Isoniazid safe to take with Propecia?

[CursedMen]

I'm thinking about starting Propecia, but I am currently on some medication that is very rough on the liver. I'm just curious if Propecia works the liver pretty hard or if the doctor would even prescribe it. The medication is called Isoniazid.

 

[Fanjeera]

Both finasteride and isoniazid inhibit cytochrome P450, so I think it will give you problems.

 

[CursedMen]

Sorry Fanjeera, one more question; do all DHT inhibitors have a correlation with lowering P450 or is it something unique to Finasteride?

 

[chicknlittle]

Finasteride is metabolized by the liver, through the cytochrome P450 system, but I see no evidence that it inhibits cytochrome p450.... And no evidence of drug interactions.

Source. http://www.druglib.com/druginfo/propecia/description_pharmacology/

Metabolism
Finasteride is extensively metabolized in the liver, primarily via the cytochrome P450 3A4 enzyme subfamily. Two metabolites, the t-butyl side chain monohydroxylated and monocarboxylic acid metabolites, have been identified that possess no more than 20% of the 5α-reductase inhibitory activity of finasteride.

Drug Interactions
(also see PRECAUTIONS, Drug Interactions)
No drug interactions of clinical importance have been identified. Finasteride does not appear to affect the cytochrome P450-linked drug-metabolizing enzyme system. Compounds that have been tested in man include antipyrine, digoxin, propranolol, theophylline, and warfarin and no clinically meaningful interactions were found.

If there is evidence to suggest otherwise please post link/ evidence..