This Wikiversity learning project allows participants to explore how hormones are used as drugs and other related drugs that modify hormonal signals in the body. The emphasis is on common health-related topics that involve hormones.
Animals have evolved such that hormone molecules are stable enough in the blood stream to be able to reach target tissues and trigger a desired response. Direct injection of hormones into the body allows for replacement of endogenous hormone by hormone applied as a drug. Since 1922, insulin has been injected and used as a drug used to substitute for low levels of endogenous insulin in diabetics. Insulin does not need to be injected directly into a blood vessel to be effective (see subcutaneous injection).
Other ways to introduce hormonal drugs into the body include:
Inhalable insulin recently became available as an alternative to injection. Other hormones are better candidates for absorption into the body because of their molecular structures. For example, progesterone can be administered either orally or topically.