does Sporanox(Itraconazole) decrease finasteride effectiveness?

[sheraz104]

I've been on Fin for 18 months or so and I believe that it slowed my hair loss. In October this year I was on Sporanox 100mg/day for 15 days and soon after starting it I started noticing thinning of hair which has continued to this day.

 

I google about itraconazole-Finasterdie interaction and found out that Itraconazole inhibits the enzyme 'CYP3A4' which metabolites Finasteride.

 

Does it mean that Itraconazole decreased the effectiveness of Finasteride?

[splitting hairs]

Hi, as a hospital pharmacist in the UK, drug interactions are something I come across on a daily basis. There is no known drug interaction between itraconazole and finasteride.

 

There are many different CYP3A4 isoenzymes so it is difficult to generalise. If, for example, itraconazole inhibited the isoenzyme that metabolises finasteride, that would actually result in finasteride staying in your body for longer and reduce hair loss.

 

I hope this makes sense.