Steroid-induced osteoporosis (SIOP) is osteoporosis arising due to use of glucocorticoids (steroid hormones) - analogous to Cushing's syndrome and involving mainly the axial skeleton. The synthetic glucocorticoid prescription drug prednisone is a main candidate after prolonged intake. Bisphosphonates are beneficial in reducing the risk of vertebral fractures.  Some professional guidelines recommend prophylactic calcium and vitamin D supplementation in patients who take the equivalent of more than 30 mg hydrocortisone ( mg of prednisolone), especially when this is in excess of three months.   The use of thiazide diuretics, and gonadal hormone replacement has also been recommended, with the use of calcitonin, bisphosphonates, sodium fluoride or anabolic steroids also suggested in refractory cases.  Alternate day use may not prevent this complication. 
Ketotifen is used by people suffering from wasting diseases partially caused by TNF-alpha. I think, however, its ability to lower TNF-alpha is going to be overshadowed by anabolic effects produced by anabolic steroids . In one study involving AIDS patients, combining Ketotifen and Oxymetholone ( Anadrol 50 ) showed that the Ketotifen didnt add much to the Oxymetholone induced weight gain (1). Hence, you are reading this profile in the "Ancilliaries" portion of this book, and not the "Fat - Burning" part, even though Ketotifen is typically used as part of a fat burning cycle including clen . Benadryl is simply too much cheaper and readily available to use Ketotifen in its place with Clen. However, for Post-Cycle-Therapy, Ketotifen and its ability to lower TNF-alpha, is a very valuable tool. You see, Hypogonadism ( low testosterone ) often accompanies elevated TNF-alpha levels (6), and after a cycle of anabolic steroids , you are going to be in a hypogonadal state, with elevated TNF-alpha. Thus, taking Ketotifen with your PCT is probably a very good idea. I recommend 1-3mgs/day before bed because this stuff will make you pretty drowsy.
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 .