Chondroitin sulfate is a dietary supplement that is most commonly used to help treat arthritis pain. Several studies have shown that it is fairly well tolerated, though some people may experience mild side effects. Some common chondroitin sulfate side effects include nausea and stomach pain, while less common ones can include rash, intestinal upset and hair loss. There may be additional risks of unwanted effects for people with certain conditions or who are taking certain medications.
In the body, chondroitin helps make up the cartilage of the joints. This flexible tissue protects the joints from outside forces, while also helping them move more easily. When a person has a common form of arthritis called osteoarthritis, the cartilage in the joints has often started to break down, causing pain and swelling. Some studies have shown that taking chondroitin sulfate supplements can help reduce this discomfort.
Several of these studies have also shown there to be few chondroitin sulfate side effects. When side effects do occur, they tend to be mild. For example, some people may experience nausea or stomach pain, especially when taking higher doses. This generally goes away when the supplement is stopped. Less common chondroitin sulfate side effects can include diarrhea, constipation, rash, headache and hair loss.
While most people do not experience unwanted effects, there are some people for whom healthcare providers generally do not recommend the use of chondroitin sulfate. These may include, for example, people with a history of prostate cancer. This contraindication comes mainly from a study that showed increased levels of chondroitin in the prostates of some men with the cancer. Based on this, some experts fear chondroitin may promote the cancer.
Another group healthcare providers generally cautions against the use of the supplement in is those who take blood-thinning medications. Chondroitin can also thin the blood, so combining the two may lead to an increased risk of bleeding. Lastly, the supplements are generally not recommended for women who are pregnant or breastfeeding, as they have not been studied in these women.
Many formulations of chondroitin sulfate also contain glucosamine sulfate, and some contain manganese. Glucosamine and manganese are both involved in joint formation, so it is thought they may help with arthritis pain in the same way that chondroitin does. Due to the fact that these ingredients are combined, side effects caused by the glucosamine or manganese may be confused for chondroitin sulfate side effects. These may include, for example, heartburn, bloating, high blood pressure and high blood sugar. If these effects are felt, a person may be able to alleviate them by taking a supplement containing only chondroitin sulfate.