I take a very small amount of ketoconazole for tinea versicolor, two pills every six months. will this small amount effect my testosterone production?

Ketoconazole : Ketoconazole is a prescription medication used by many dermatologists for tinea versicolor. It is can lead to decreased steroidogenesis and testosterone production, but a few pills twice a year should have minimal effect on those processes. It should only be used under the guidance of a dermatologist or other capable physician and can be quite effective for tinea versicolor in many cases. I hope that helps.

Probably temporary: From my reading on your questions, orally administered ketoconazole can indeed affect testosterone synthesis. However, since you only take it every six months, even if you take a "hit" in terms of testosterone synthesis for a few days to a week or so, you ought to be fine.