Prepare your questions
Pregnancy, other medicines, and sport
Some safety questions have no study answer. Sport has a written ban. Check what each means for your situation.
In the US, medicines are reviewed by the Food and Drug Administration, known as the FDA.
Sport has an explicit ban
WADA stands for World Anti-Doping Agency, which publishes rules against banned substances in sport.
- As of September 2026, the WADA list prohibits TB-500 during and outside competition, and the US college sports list also names it.
- The WADA list taking effect on January 1, 2027 keeps the same TB-500 entry.
- Ask the organisation governing your sport about the rules that apply to you.
Bring the unanswered health questions to the visit
Other medicines: the record is missing
Bring your medicines and health history to the conversation. Ask how they affect the options being discussed.
- As of September 2026, no FDA-reviewed label for TB-500 describes its effects with other medicines or identifies who must avoid it.
- There is no FDA-reviewed TB-500 information for pregnancy, breastfeeding, or children, and FDA reviewers found no animal pregnancy studies.
- Ask how that lack of information affects the options for your situation.
The cancer question remains open
These concerns come from studies of the whole protein, rather than TB-500.
- Cell and mouse studies tested tumour cells made to produce more of the whole thymosin beta-4 protein. These cells moved more, and their tumours grew more blood vessels. Moving tumour cells can spread cancer to other places. These studies raise questions about cancer, but they did not test TB-500.
- Those findings do not establish that TB-500 causes cancer, and TB-500 cancer risk has not been studied.
- Ask a doctor or another licensed health professional what these unanswered questions mean for your health history.