A secretagogue is a substance that stimulates the pituitary gland to produce human growth hormone. This has been an intriguing avenue of research. Over the last twenty years, several short-chain, orally absorbable compounds have been investigated. Containing as few as three (commonly six to eight) amino acid molecules, some compounds have been shown to stimulate the production of significant amounts of human growth hormone. Of the truly effective molecules, the pituitary gland was stimulated in a too broad manner, and levels of other hormones that are not desirable were also raised. Most unfortunately, the most common accompanying hormone rise was seen in cortisol levels. In a way, cortisol is the nemesis of human growth hormone, antagonizing the beneficial effects of human growth hormone action. These secondary hormonal changes have severely limited the general role secretagogues may play in human growth hormone supplementation, and have stymied the ability of pharmaceutical research to develop useful compounds. To date, none have proven to be consistent enough in their actions or safety profile to warrant a specific product release.
Some claimed secretagogues are available in the over-the-counter market; while these products are generally safe, but in general do not demonstrate a certain human growth hormone response in every individual. They seem to have their greatest effectiveness in young (under age 35) and highly athletic people, and require high dose to generate a meaningful response. The number of people who respond is typically around 35%, and in those who respond there is only a 10-30% increases in level. With advancing age there is a progressively smaller response rate and magnitude of response. Exceptions exist, and it is regarded as a safe category of compound to use in a trial, after a baseline hormone level is established and, after a three- month course of secretagogues, additional retesting of hormone levels is done. A total reevaluation should be made after no more than 6 months to determine effectiveness. Only if there is objective as well as subjective improvement documented should use of the product be continued. Even an FDA approved injectable secretagogue is of limited value even in very young people. The secretagogue market brings to mind an important caveat regarding any medical or health directed program: The most important aspect of any medical/health undertaking is the open exchange of information; people should know precisely what they put into their bodies. Even patented drugs must disclose what they contain so appropriate decisions can be made regarding safety. Rule number one with secretagogues should be that any marketing company must tell the consumer exactly what he or she is ingesting.