The most commonly used AAS in medicine are testosterone and its various esters (but most commonly testosterone undecanoate , testosterone enanthate , testosterone cypionate , and testosterone propionate ),  nandrolone esters (most commonly nandrolone decanoate and nandrolone phenylpropionate ), stanozolol , and metandienone (methandrostenolone).  Others also available and used commonly but to a lesser extent include methyltestosterone , oxandrolone , mesterolone , and oxymetholone , as well as drostanolone propionate , metenolone (methylandrostenolone), and fluoxymesterone .  Dihydrotestosterone (DHT; androstanolone, stanolone) and its esters are also notable, although they are not widely used in medicine.  Boldenone undecylenate and trenbolone acetate are used in veterinary medicine . 
Tren is an extremely androgenic hormone, and as a result well known for promoting androgenic side effects. Hair loss and acne in men who are predisposed are both possible. Body hair growth is also possible. If you are not genetically predisposed no amount of Tren on earth with cause these issues. The androgenic side effects of Tren are truly based on genetic response. When it comes to hair loss, if you are predisposed to male pattern baldness, meaning at some point you’re going to lose your hair regardless of steroid use , Tren is one of the fastest ways to ensure you lose your hair a little sooner.
Virilization is a serious androgenic side effect of Tren. It is very difficult for a woman to use Tren without some level of virilization and makes it a steroid that’s almost never recommended for female use.
Important Note: The 5-alpha reductase enzyme does not metabolize the Trenbolone hormone. This means 5-alpha reductase inhibitors like Finasteride will not affect the androgenicity of the hormone.