4-Hydroxytestosterone (4-OHT, 4,17beta-dihydroxy-4-androstene-3-one) is a
legal steroidal compound that is relatively new to the market. Unlike prohormones,
4-OHT does not require enzymatic conversion to have an anabolic effect. It
was first patented by G.D. Searle & Co. in 1955, but it did not reach
the commercial market, and has recently become available as a dietary supplement.
Chemically, 4-OHT is testosterone with a hydroxy group at the four position,
making it most similar to the steroid clostebol, which has a chloro group
at the four position. These two compounds are also very similar in effect.
4-OHT has moderate anabolic, mild androgenic, and anti-estrogenic properties.
All in all, it can be expected to be associated with very few side effects,
but this also comes at the expense of reduced anabolic activity. In the levator
ani assay, 4-OHT is .65 times as anabolic and .25 times as androgenic as
testosterone propionate. The reason that this compound has such low androgenic
activity is that the modification at the 4 position prevents DHT conversion.
In vitro, 4-OHT is actually a weak inhibitor of 5-alpha reductase. This weak
androgenic effect is ideal for those who want to avoid or minimize side effects
such as baldness, acne, and BPH. 4-OHT also has the benefit of having anti-estrogenic
effects, which will eliminate chances of estrogen levels increasing, which
can lead to side effects such as extra water retention and gyno. 4-OHT itself
is a weak inhibitor of the aromatase enzyme which converts testosterone into
estrogen, and a metabolite, 4-hydroxyandrostenedione (formestane), is a potent
aromatase inhibitor. It should be emphasized that both androgenic and estrogenic
effects can be beneficial for bodybuilders, it is simply a matter of how
much side effects one wishes to tolerate.
Like most steroids, 4-OHT has low oral bioavailability and should be taken
through a different route. Another reason why oral administration is not
ideal is that, like clostebol, 4-OHT has a very short half-life. Those who
inject usually use it every day or every other day totalling 300-700 mg weekly,
stacked with other substances. Doses for transdermal administration should
be in the range of 150-300 mg daily, and this is once again assuming one
is stacking it with other steroids or prohormones. Using it as a standalone,
optimal doses are probably considerably higher. 4-OHT has been most commonly
stacked with 4-AD and 1-testosterone, although there are theoretical reasons
why it may be beneficial to stack it with many substances – it will generally
reduce estrogenic side effects, while adding anabolism without significantly
contributing to androgenic side effects.
If you have any questions or comments regarding this article, please email
dvdtlsn@bulknutrition.com.
No part of this article may be reproduced in any form without the permission of David Tolson or Mike McCandless.
