Steroid isolation , depending on context, is the isolation of chemical matter required for chemical structure elucidation, derivitzation or degradation chemistry, biological testing, and other research needs (generally milligrams to grams, but often more  or the isolation of "analytical quantities" of the substance of interest (where the focus is on identifying and quantifying the substance (for example, in biological tissue or fluid). The amount isolated depends on the analytical method, but is generally less than one microgram.  [ page needed ] The methods of isolation to achieve the two scales of product are distinct, but include extraction , precipitation, adsorption , chromatography , and crystallization . In both cases, the isolated substance is purified to chemical homogeneity; combined separation and analytical methods, such as LC-MS , are chosen to be "orthogonal"—achieving their separations based on distinct modes of interaction between substance and isolating matrix—to detect a single species in the pure sample. Structure determination refers to the methods to determine the chemical structure of an isolated pure steroid, using an evolving array of chemical and physical methods which have included NMR and small-molecule crystallography .  :10–19 Methods of analysis overlap both of the above areas, emphasizing analytical methods to determining if a steroid is present in a mixture and determining its quantity. 
However, the Anavar steroid was discontinued by Searle in 1989, due to the bad press brought on by bodybuilders abusing the drug. It was later reintroduced to the world market as Oxandrin in 1995, but it remains a controlled substance under US law. The current manufacturer of oxandrolone holds all the rights to their medicine, and that’s why it is very rare to find oxandrolone today. It’s still called Anavar by most people, and it’s very hard to buy. Even if you do find Anavar for sale, the law of supply and demand inevitably results in a rather exorbitant price for the steroid.
The use of anabolic steroids such as Winstrol may be associated with serious adverse reactions, many of which are dose related. Patients should be placed on the lowest possible effective dose. Medications that may interact with Winstrol include anticoagulants (blood thinners), insulin , or an oral diabetes medicine. Tell your doctor all medications you are taking. Winstrol is known to cause birth defects in a fetus. Do not take this medication if you are pregnant or could become pregnant during treatment. It is not known whether Winstrol is excreted in human milk. Many drugs are excreted in human milk and there is the potential for adverse reactions in nursing infants from anabolic steroids. Consult your doctor before breastfeeding.