My doctor suggested that i take donna (glucosamine). is this drug safe ?

Safe: Unless you have a shellfish allergy, glucosamine is generally a safe dietary supplement. Its efficacy has been argued over for years. The goal of taking it is to allow the body's cartilage to repair itself and stay healthy. If you have been diagnosed with osteoarthritis and you want to try it, take it for three months and see if it works to alleviate pain or stiffness.