Guanosine

Guanosine is a nucleoside—a building block of nucleic acids—that occurs naturally in the body and in some plant sources. In skincare formulations, it functions primarily as a skin conditioning agent, helping to maintain skin texture and hydration.The ingredient works at a cellular level, supporting processes involved in energy production and cellular signalling within the skin. Its role in skincare is largely supportive rather than transformative, making it a complementary addition to broader skincare routines.

Guanosine participates in nucleic acid synthesis and energy metabolism within skin cells. As a nucleoside, it can be incorporated into RNA and DNA, supporting normal cellular maintenance and repair processes.At a molecular level, guanosine may also influence cellular signalling pathways that regulate skin barrier function and inflammatory responses, though the extent of these effects in topical skincare remains an area of ongoing investigation.

Guanosine is typically used as a supporting ingredient rather than a primary active, so you'll most often encounter it in serums, moisturisers or multi-ingredient formulations. Use as directed on product packaging. Since it is gentle and non-irritating, it can be incorporated into most skincare routines without specific timing concerns.

Guanosine is generally well-tolerated and considered safe for topical use. No significant adverse effects or contraindications are widely documented.