Other significant adverse effects of testosterone supplementation include acceleration of pre-existing prostate cancer growth in individuals who have undergone androgen deprivation; increased hematocrit , which can require venipuncture in order to treat; and, exacerbation of sleep apnea .  Adverse effects may also include minor side-effects such as acne and oily skin, as well as, significant hair loss and/or thinning of the hair, which may be prevented with 5-alpha reductase inhibitors ordinarily used for the treatment of benign prostatic hyperplasia , such as finasteride .  Exogenous testosterone may also cause suppression of spermatogenesis , leading to, in some cases, infertility.  It is recommended that physicians screen for prostate cancer with a digital rectal exam and prostate-specific antigen (PSA) level before starting therapy, and monitor PSA and hematocrit levels closely during therapy. 
In summary, whichever form of tren you use, be cautious of the product and individual. Some legit brands are: Quality Vet, Denkall, and the most recent thus far Animal Power veterinary brands. They all currently make very good and pure versions of trenbolone (you will have to look but you can find various esters available also). Novice dosage is around 2-3cc's a week for a total of 150-225mg/week. Upper level advanced and very seasoned users may use upwards of 4-5cc's a week. If you were my family member, I would tell you to not use more than 3cc/week and not to stay on any form of tren for longer than 12 weeks (three month cycle).