Products
Glucosamine is commercially available in capsule, tablet, and liquid forms, among others. Glucosamine has not yet been approved as a drug in many countries and is not reimbursed by basic insurance. This is in contrast to [chondroitin sulfate.
Structure and properties
D-glucosamine or 2-amino-2-deoxy-β-D-glucose (C6H13NO5, Mr = 179.17 g/mol) is an amino sugar that is readily soluble in water and hydrophilic organic solvents. Its structure is identical to that of glucose except for the amino group, which replaces a hydroxy group. In pharmaceuticals, it is present as glucosamine sulfate or glucosamine hydrochloride. Glucosamine is usually obtained from marine sources, from shellfish such as crabs and shrimp, because the chitin contained in the exoskeleton is a polymer of -acetyl-D-glucosamine. Glucosamine can also be produced synthetically. The so-called “organic” or “ecological” glucosamine comes from the fungus , which thrives on corn crops and is also suitable for people allergic to shellfish and vegetarians. Glucosamine is a component of N-acetylglucosamine, hyaluronic acid, heparins, chondroitin sulfate and glycosaminoglycans.
Effects
Glucosamine (ATC M01AX05) is an endogenous substance needed to build cartilage components, such as glycosaminoglycans or glycoproteins. It may be analgesic, anti-inflammatory, cartilage-protective, cartilage-building, and may alleviate the symptoms of osteoarthritis and delay its progression. Glucosamine is relatively well studied compared to other nutritional supplements. However, its clinical efficacy is highly controversial and has not been clearly proven to date. The mechanism of action is unknown. It is possible that glucosamine acts as a substrate for the synthesis of proteoglycans, stimulates their synthesis, or inhibits inflammatory mediators.
Indications for use
Glucosamine is taken as a food supplement to relieve the symptoms of osteoarthritis, for example, knee joint arthrosis. It is not approved as a drug for this purpose in many countries.
Dosage
According to the manufacturer’s instructions. The usual daily dose is up to 1500 mg, administered as a single dose or divided into three doses of 500 mg each, with meals and sufficient water. Possible improvement of symptoms is delayed until after 4 to 8 weeks of regular use.
Contraindications
Glucosamine should not be taken in cases of hypersensitivity. Some products are made from shellfish and are not suitable for people with shellfish allergy. Treatment of children and adolescents under 18 years of age and pregnant or nursing women is not recommended due to lack of data. In the elderly, impaired liver and kidney function, people with diabetes mellitus (glucose intolerance), risk of cardiovascular disease and bronchial asthma, glucosamine should be used only with caution and under medical supervision.
Interactions
There are insufficient data on drug-drug interactions. Interactions with vitamin K antagonists such as warfarin (oral anticoagulants) have been described. Glucosamine may increase serum concentrations of tetracyclines, which could increase their adverse effects.
Adverse effects
Glucosamine appears to be generally well tolerated. Possible adverse effects include gastrointestinal symptoms such as nausea, vomiting, abdominal pain, heartburn, taste disturbances, diarrhea, and constipation. Headache, fatigue and allergic reactions have also been reported. In rare cases, hypercholesterolemia may possibly occur or bronchial asthma and diabetes mellitus may be worsened. However, this has not been proven with certainty.
