Chemical Formula: C27H40O3 Description Testosterone cypionate is a synthetic derivative of testosterone in the form of an oil-soluble 17 (beta)-cyclopentylpropionate ester. Its benefit compared to other testosterone derivatives is the slow rate of release after injection and longer half-life. The characteristics of testosterone cypionate and testosterone enanthate are very similar, therefore both of them tend to be interchangeable. It was developed by the company Pharmacia and Upjohn and FDA approved on July 25, 1979. Mechanism of action The effects of testosterone in humans and other vertebrates occur by way of two main mechanisms: by activation of the androgen receptor (directly or as DHT), and by conversion to estradiol and activation of certain estrogen receptors. Free testosterone (T) is transported into the cytoplasm of target tissue cells, where it can bind to the androgen receptor, or can be reduced to 5α-dihydrotestosterone (DHT) by the cytoplasmic enzyme 5α-reductase. DHT binds to the same androgen receptor even more strongly than T, so that its androgenic potency is about 2.5 times that of T. The T-receptor or DHT-receptor complex undergoes a structural change that allows it to move into the cell nucleus and bind directly to specific nucleotide sequences of the chromosomal DNA. The areas of binding are called hormone response elements (HREs), and influence transcriptional activity of certain genes, producing the androgen effects. Side effects Testosterone cypionate injectable solution doesn’t cause drowsiness, but it can cause other side effects. More common side effects The more common side effects of testosterone cypionate can include:
acne
pain and swelling at injection site
hair growth
gynecomastia (breast enlargement)
more frequent erections
erections that last longer than normal
mood swings
headache
decrease in sperm count when the drug is used at high doses
If these effects are mild, they may go away within a few days or a couple of weeks. If they’re more severe or don’t go away, talk to your doctor or pharmacist.