The green-lipped mussel, or perna canaliculus, is a bivalve mollusk native to New Zealand. It is found mainly below the intertidal zone at a depth of about 33 feet (10 meters). An extract of this mollusk is said to have medicinal uses.
Most green-lipped mussels can be found in ocean waters of the northern and central parts of New Zealand which feeds on various species of phytoplankton. They are also found in Australia, and are considered an introduced nuisance. The green-lipped mussel is an important commercial mollusk.
It is possible for the green-lipped mussel to reach a length of 10 inches (26 cm). Harvesting length is typically about four inches (10 cm). Juveniles are bright green in color, and adults are purple or black. Commercial adults are green or yellow-brown with brown stripes or spots. All varieties have a distinctive green lip along the inner edge of the shell.
In the 1960s, researchers from the United States and Great Britain conducted studies to test the use of the green-lipped mussel as a treatment for cancer. The mussels had no effect on the cancer, but patients also suffering from arthritis reported improvements in joint symptoms. This lead to later studies of the green-lipped mussel as a treatment for osteoarthritis, rheumatoid arthritis, and asthma. Some of these studies have shown good results, while others show poor or mixed results. Not enough evidence exists for this to be officially labeled as a treatment option.
The healing properties of the green-lipped mussel are thought to come from the polysaccharide glycosaminoglycan. It is available as both a lipid extract and a freeze dried supplement. Other versions of the drug exist but may not be as effective.
During clinical trials, the dose given of the liquid drug was 1,500 milligrams per day. The dose for the freeze dried version ranged from 900 to 1,380 milligrams per day. For patients with asthma, the dose was 200 milligrams per day of the liquid version.
Most people who are interested in using green-lipped mussel extract can do so safely, but there are some possible side effects. Nausea, diarrhea, and liver problems may occur. There is evidence that it causes slow growth or delayed birth of the fetus when taken by pregnant women. Patients who are allergic to shellfish and those with liver impairment should not use these preparations. Anyone wishing to use green-lipped mussel extract or any other health supplement should first consult a health care provider.