Cypionate and propionate are both forms of testosterone used in hormone therapy in males who do not produce enough testosterone naturally. Both substances are considered steriods and are illegal to use without prescription from a doctor. The benefits and possible side effects from using these substances are the same; however, there are a number of differences between the two types of testosterone.
The speed at which the body is able to begin utilizing the testosterone is one consideration in whether cypionate or propionate are utilized. Propionate is the faster-reacting ester, which is the chemical makeup of the testosterone, of the two steriods. Cypionate reacts more slowly within the body before the benefits of taking the steriods are seen.
Frequency of Doses
While propionate is the faster-acting steriod, the downside to this is that it wears off faster than the slower-reacting cypionate. This results in the requirement to take propionate more often to achieve the same effects. For example, propionate injections are completed once every three days. Cypionate injections are required only on a weekly basis.
The ester added to the testosterone molecule to make it more soluble in oil is different for cypionate and propionate. Cypionate ester is OCOCH2CH2, which makes it the longest ester chain available. By comparison, propionate is the shortest ester available, with only three carbon molecules in a chain. These different ester chains are the reason why the propionate reacts faster and must be taken more often than cypionate.
Both steriods are administered through an injection but propionate injections are much more painful than those of cypionate. This again is in relation to propionate's short ester chain. The shorter the ester chain, the more painful the injection. Muscles around the injection site can become swollen and very painful. Propionate injects also tend to be in lower dosages than cypionate because increasing the dosage also increases the pain of the injection.