What is Glycine?

Glycine is the simplest of the 20 different amino acids used as building blocks to make proteins for your body. It works in concert with glutamine, a substance that plays a major role in brain function. Glycine has shown some promise as an aid in the treatment of schizophrenia and may have other uses related to the brain as well, such as enhancing mental function .

Several studies have evaluated glycine as a supportive treatment for schizophrenia . ¹ According to some, but not all, of these studies, high doses of glycine (from 15 to 60 g daily) might augment the effectiveness of medications used for this condition. The one notable exception is clozapine (Clozaril); one study suggest that glycine may actually decreasethe effectiveness of this drug (see Safety Issues below).

One large double-blind study suggests that low doses of glycine may be helpful for limiting the spreading brain damage that occurs during stroke . ² However, there are also theoretical concerns that glycine could increase such damage (see Safety Issues ), so you should not try this treatment except under physician supervision.

A small double-blind study found...

Safety Issues

No serious adverse effects from using glycine have been reported, even at doses as high as 60 g per day. One participant in the 22-person trial described above developed stomach upset and vomiting, but it ceased when the glycine was discontinued.

In contradiction to the study on strokes mentioned above, theoretical concerns have been raised that suggest glycine might actually increase brain injury in strokes. ³ In fact, drugs that block glycine have been investigated as treatments to limit stroke damage. ⁴ However, the authors of the study on strokes described above make an argument that suggests the overall effect of glycine is protective. ⁵ Until this controversy is settled, prudence suggests not using glycine following a stroke, except on the advice of a...