Common side effects of Osteo Bi-Flex include stomach pain, bloating, gas, nausea, diarrhea and constipation. Those taking the supplement could also experience puffy eyelids and hair loss, according to Drugs.com.
Severe side effects associated with Osteo Bi-Flex include difficulty breathing, hives, irregular heartbeat, or swelling in legs, face, lips, tongue or throat. These severe side effects require immediate medical attention, warns Drugs.com. Osteo Bi-Flex, a joint health supplement, has not received approval from the U.S. Food and Drug Administration as of 2015.
One of the supplement's ingredients, boswellia serrata, is a tree resin that potentially has anti-inflammatory properties, notes the Indian Journal of Pharmaceutical Science.