steroid vs androgen therapy

[jcorbett]

Does anyone know the difference between these? On the following site, topical steroids and androgen therapy are discussed as possible solutions (investigational agents ...near the bottom of the page), but testosterone is not in the steroid category, it is in the androgen category. I am curious about this because I am using the testosterone cream and really like it. I don't want to give it up, yet I am concerned because some posters stated their doctors didn't like the idea. I asked three doctors, and they all said the amounts you applied to the eye in this cream were too minute to be of any concern. What exactly is androgen therapy, and how does that differ from steroids?
http://www.revoptom.com/index.asp?Ar...248/lesson.htm

[DrG]

Testosterone is an androgen is a steroid. Cortisol, cortisone, hydrocortisone, and prednisone are steroids. They are all steroids because of their common chemical structures, although their functions are completely different. Cortisol and its analogues are used to treat inflammation.

Androgens (testosterone) appear to play a role in homeostasis of the lacrimal system. Topical androgens are being investigated for the treatment of dry eye, in which case they would act directly on the androgen receptors of the tear glands. It is not known whether the testosterone in the eye cream acts directly on the tear glands, or indirectly via absorption through the skin into the blood stream.

The term "steroid" is sometimes confusing.

DrG

[Cindy]

It is not known whether the testosterone in the eye cream acts directly on the tear glands, or indirectly via absorption through the skin into the blood stream.

I don't get this. If the cream is applied topically, how can it act directly on the tear glands? Wouldn't it have to be absorbed through the skin into the blood stream? How could it go directly to the tear glands?

Would an androgen eyedrop go directly to the tear glands? Or through the blood stream first?

[DrG]

I don't get this. If the cream is applied topically, how can it act directly on the tear glands? Wouldn't it have to be absorbed through the skin into the blood stream? How could it go directly to the tear glands?

Would an androgen eyedrop go directly to the tear glands? Or through the blood stream first?

Permit me to expand the concept. As mentioned, there is a topically applied androgen in phase III clinical trials. As with all topically applied eye medications, the effects are intended to be local via direct action on the androgen receptors of the tear glands. I am referring now to the testosterone cream that is currently available by prescription through a compounding pharmacy.

The instructions for using the testosterone cream suggest applying it to the periorbital region, i.e. around the eyes, eyelids, etc. If only the systemic effect was intended, the cream could just as well be applied anywhere on the body. Since I am not the inventor of the cream, I can only surmise that applying the cream to the eye would involve several mechanisms: systemic via transdermal absorption; local via direct action on the androgen receptors of the tear glands; direct action of the lipid in the vehicle on the tear film.

DrG