Anabolic steroid implants are allowed for veterinary use. But if someone diverts this for use in humans, it will be deemed as a distribution of a Schedule III drug leading to prosecution. The law on trenbolone differs in other countries. For instance, in Canada it is a Schedule IV drug. In Canada, all anabolic steroids are classified as Schedule IV drugs. In the UK, anabolic steroids are classified as Class C substances. Their possession can lead to a 2 year jail term, while their production and supply can lead to a 14 year jail term. But many countries do not have strict laws. In some places, you can even buy it over the counter.
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.
In a study of 1,685 patients treated with CPA, elevated liver enzymes were seen in 10% of patients at a dosage of 50 mg/day and in 20% of patients at a dosage of greater than 100 mg/day.  A study of 2,506 patients given 18–136 mg/day for less than 48 months per patient reported a rate of %.   In a trial of 89 prostate cancer patients who received high-dose CPA for 4 years, there were elevated liver enzymes in % of the patients.  Yet another study of 105 patients found a hepatotoxicity rate of %, with serious hepatic injury occurring in %.  In 2002, it was reported that there were 18 case reports of CPA-associated hepatitis in the medical literature, with 6 of the cases resulting in death.  In addition, a review article cited a report of 96 instances of hepatotoxicity that were attributed to CPA, and 33 of these instances resulted in death.  Moreover, a 2014 review found that 15 cases specifically of CPA-induced fulminant (sudden-onset and severe) liver failure had been reported to date, with only one of these cases not resulting in death.  As such, the prognosis of CPA-induced liver failure is death.