Testosterone Cypionate

Testosterone cypionate is testosterone esterified with a cyclopentyl group, which slows absorption and turns it into a depot oil. A single injection holds a stable level for roughly a week and a half to two weeks, which is why it sits at the centre of most testosterone protocols.

What makes it different from enanthate

Honestly, not much at the receptor level - both are long-acting depot esters and the practical difference is the injection interval and the oil carrier. Cypionate tends to be a touch more stable in storage and slightly less painful than some carriers, which is why bodybuilders who react badly to enanthate often switch to cypionate and feel the difference immediately.

What to check on the label

• Concentration per ml, printed clearly, with cypionate named as the ester.
• Clear oil, no particles, no separation on standing.
• Expiry date, batch number and an intact seal.
• Storage away from heat - a warm car destroys cypionate like it destroys anything else.