Testosterone propionate is a common oil-based injectable testosterone. The added propionate extends the activity of the testosterone but it is still comparatively much faster acting than other testosterone esters such as cypionate and enanthate. While cyp and enanthate are injected weekly, propionate is most commonly injected at least every third day to keep blood levels steady. For strength and muscle mass gains, this drug is quite effective. With propionate, androgenic side effects seem somewhat less pronounced than with the other testosterones, probably due to the fact that blood levels do not build up as high. Users often report less gyno trouble, lower water retention and commonly claim to be harder on prop than with the others.