Hyaluronic acid, otherwise known as hyaluonan, is a protein found throughout the body in tissues and synovial fluid of joints. It acts as a binding, lubricating and protective agent. The amount of hyaluronic acid in the body can diminish as a natural process of aging or following exposure to environmental factors such as sunlight. Hyaluronic acid can be used in the treatment of osteoarthritis, prevention of adhesions after surgery and in dermal fillers.
Topical Side Effects
Hyaluronic acid has been used as a drug delivery vehicle in various methods of administration, including topical application. It can be combined with diclofenac for the treatment of actinic keratosis, and as a gel it has been found to be safe, well tolerated and effective. However, some individuals are susceptible to reactions to hyaluronic acid or other additives. Reactions can include itching, acne, rashes and redness.
Injectable Side Effects
Hyaluronic acid has been used in the treatment of osteoarthritis. Novaes and colleagues in the “International Journal of Pharmacology Research” in 2005 showed in 365 patients that intra-articular hyaluronic acid administration was well tolerated, with only 2.5 percent of patients showing a non-serious side effect. Hyaluronic acid, in the form of a gel, can be used as a filler to improve deformities. A study by Hedén and colleagues in 2009 and published in "Aesthetic Plastic Surgery" showed that the use of this gel led to no serious side effects, although some individuals had mild to moderate, short-lived reactions such as swelling, tenderness and redness. Some patients did suffer a fever and were treated with antibiotics. However, a study published in 2010 in “Journal of Plastic and Reconstructive Aesthetic Surgery” described complications following an injectable form of hyaluronic acid after breast surgery -- side effects that included infection and capsular contraction that required further surgery.
Known Side Effects
Though side effects are rare, they include bruising, rash, acne, swelling and pain. Severe side effects can include diarrhea, dizziness, cough, sneezing, swelling of the face and lips and alteration in skin color. Individuals who are known to have multiple allergies should avoid the use of hyaluronic acid.
A number of other drugs or supplements should be avoided in tandem with hyaluronic acid, as they have been shown to increase the risk of some of the side effects such as bruising. These include vitamin E, St. John's Wort, aspirin and other non-steroidal anti-inflammatory drugs.