Injectable steroids are injected into muscle tissue, not into the veins. They are slowly released from the muscles into the rest of the body, and may be detectable for months after last use. Injectable steroids can be oil-based or water-based. Injectable anabolic steroids which are oil-based have longer half-life than water-based steroids. Both steroid types have much longer half-lives than oral anabolic steroids. And this is proving to be a drawback for injectables as they have high probability of being detected in drug screening since their clearance times tend to be longer than orals. Athletes resolve this problem by using injectable testosterone early in the cycle then switch to orals when approaching the end of the cycle and drug testing is imminent.
Valproic acid was first synthesized in 1882 by Beverly S. Burton as an analogue of valeric acid , found naturally in valerian .  Valproic acid is a carboxylic acid , a clear liquid at room temperature. For many decades, its only use was in laboratories as a "metabolically inert" solvent for organic compounds. In 1962, the French researcher Pierre Eymard serendipitously discovered the anticonvulsant properties of valproic acid while using it as a vehicle for a number of other compounds that were being screened for antiseizure activity. He found it prevented pentylenetetrazol -induced convulsions in laboratory rats .  It was approved as an antiepileptic drug in 1967 in France and has become the most widely prescribed antiepileptic drug worldwide.  Valproic acid has also been used for migraine prophylaxis and bipolar disorder. 
Oral estradiol valerate is used primarily in Europe , under the brand name Progynova.  Although previously available in the United States ,  oral estradiol valerate is no longer available in this country (except in combination with dienogest as a combined oral contraceptive under the brand name Natazia).  Intramuscular estradiol valerate is available under the brand name Delestrogen in the .  and Canada and under the brand name Progynon Depot in Europe and elsewhere in the world.  In the ., it is available in formulations of 10 mg/mL, 20 mg/mL, and 40 mg/mL in oil (as Delestrogen, as well as generics ).  The only other injectable formulations of estrogen available in the . are estradiol cypionate (5 mg/mL in oil) and conjugated estrogens ( Premarin ) (25 mg/vial in solution).