is a really interesting variant of Dihydrotestosterone.
modified at the A-ring (thereís 4 rings on steroids usually), to make
another whole ďringĒ called a pyrazol group. Thereís only one other
steroid Iíve ever seen that has a similar modification. Winstrol is a
commonly used anabolic steroid for cutting cycles, and certainly itís
been shown clinically to not elicit any really impressive weight gain
(if any at all) 
usually seen as a less expensive alternative
And just like Anavar and
derivations, it can not convert to estrogen at any dose, and
is not progestenic.
As with Proviron, another DHT derived oral
Winstrol may be
useful in any cycle (perhaps even bulking) in order to lower Sex
Hormone Binding Globulin.
One of the
properties of Winstrol is itís
profound ability to lower SHBG
more than other steroids. This
could make more testosterone (or whatever steroids
likely to remain unbound and therefore active.
A nice quality look can be attained with the use of Winstrol in a
decent cutting cycle, but having it in a heavy bulking cycle could end
up being problematic, as people often get sore joints from using it for
extended periods of time. Stanozolol is an alkylated compound, which
means that itís been specifically altered to endure the first pass
through the liver without being destroyed.
And since the injectable version is simply a suspended version of the
same compound, itís able to be orally ingested instead of injected.
However, since it is alkylated, it is also pretty liver toxic, having
one of the worst hepatoxicity (mg for mg) of any steroid
As regards cholesterol, and itís quite harsh on both LDL and HDL 
and cardiac hypertrophy could be a possible concern with
Winstrol also. 
to say, most men donít use Winstrol for
very long in their cycles, and limit it to about 6 weeks or so at
50-100mgs every day (and yes, the same dosing applies for the
injectable or the oral). Women typically use 10-25mgs per day, with the
high end of that being reserved for competitive bodybuilders and figure
competitors. Of course, acne, hairloss and (in women) clitoral
hypertrophy are very real concerns.
As it is available in both an oral form as well as an injectable form,
and both contain the same compound, you might find this next part odd,
but the injectable route actually produces greater nitrogen retention. 
Another counterintuitive fact about Winstrol is that although the
anabolic rating of this product is very high, not too many people
report much weight gain off of it. Also, it has a very weak Androgen
Receptor binding ability 
, which is
kind of odd for a drug with
Winstrolís effects. unusual for
a ďcuttingĒ steroid. Protein synthesis is reasonably high with Winstrol 
although weight gain is low, paradoxically.
In all, this is a very odd compound, from a chemical/biological point
of view. My personal experience with it was that it can be used as a
cheap substitute for Anavar, although I prefer the latter. Also, the
injections hurt like hell..
Winstrol is available widely on the black market from a variety of
sources, including veterinary companies as well as human grade
pharmaceutical houses. As is always the case, underground labs produce
it very cheaply, and itís available as paper anabolics as well. Going
rate at the time of this writing is roughly under $100 for a 10-200ml
bottle of 100mg/ml concentration, and is basically
the same for a bottle of 100 x 10mg tablets.