Glucosamine is marketed for use in osteoarthritis to relieve pain and improve joint mobility.

What is glucosamine?

  • Glucosamine is a chemical sugar found naturally in the body.
  • It helps in the formation and repair of cartilage in joints. Cartilage is the slippery, shock absorbing tissue that covers the ends of bones in a joint. It allows the bones to move smoothly against each other.
  • Glucosamine is also available as a nutritional supplement that can be bought from pharmacies and health shops. 
  • The glucosamine in manufactured supplements is usually obtained from shellfish such as crab, lobster or shrimp shells, but some supplements are made from a plant form of glucosamine.
  • In New Zealand glucosamine is not registered as a medicine but is considered a health supplement.
  • Glucosamine is available in two different salt forms –  glucosamine sulphate and glucosamine hydrochloride.
  • Glucosamine is often sold in combination with another supplement called chondroitin.

What is glucosamine used for?

Glucosamine is marketed for use in osteoarthritis to relieve pain and improve joint mobility.

Does glucosamine work?

  • The scientific evidence around the use of glucosamine is not strong.
  • Glucosamine sulphate has been found to lessen the progression of osteoarthritis and provide pain relief and improved joint mobility.1,2
  • The evidence for the use of glucosamine hydrochloride is less clear.


The recommended dose is:

  • glucosamine sulphate: 1500mg per day
  • glucosamine hydrochloride: 1500mg per day (note, glucosamine sulphate is suggested to be more effective).

The effect of glucosamine is not immediate. You may need to take the supplements for four to six weeks before you notice any improvement. If there is no change in your symptoms by then, it’s likely the supplements will not be of benefit for you and it’s advisable you talk to your doctor about other ways of managing your arthritis.

What are the side effects of glucosamine?

Glucosamine is not known to be cause any major side effects. Common mild side effects include:

  • nausea (feeling sick)
  • indigestion, stomach upset
  • stomach pain or cramps
  • diarrhoea (loose stool).

Since glucosamine is obtained from shellfish, people with seafood allergies should be careful.

Learn more

Complementary therapies and products Arthritis New Zealand
Glucosamine and chondroitin Arthritis information Sheet, Arthritis Australia
Glucosamine Patient Info, UK
Glucosamine & chrondroitin factsheet OrthoInfo American Academy Orthopaedic Surgeons


  1. Richy F, Bruyere O, Ethgen O, Cucherat M, Henrotin Y, Reginster JY. Structural and symptomatic efficacy of glucosamine and chondroitin in knee osteoarthritis: a comprehensive meta-analysis. Arch Intern Med. 2003 Jul 14;163(13):1514-22. 
  2. Towheed TE, Maxwell L, Anastassiades TP, Shea B, Houpt J, Robinson V, Hochberg MC, Wells G. Glucosamine therapy for treating osteoarthritis. Cochrane Database Syst Rev. 2005 Apr 18;(2):CD002946. 

Credits: Sandra Ponen, Pharmacist. Last reviewed: 14 Apr 2015