The product details at a glance
Flexaten is sold as a food supplement with 30 capsules per pack. The directions state two capsules daily, which works out at 15 days of use per pack. Each capsule declares glucosamine sulphate, MSM, horsetail extract and vitamin C.
These figures come from the product information available. The labelling on the pack you actually receive always takes precedence, because formulations and quantities can differ between batches and markets.
What the four components are
Glucosamine sulphate is the sulphate form of an amino sugar. The form matters because sulphate and hydrochloride differ in how much pure glucosamine they contain. MSM is an organosulphur compound with no authorised EU health claim.
Horsetail extract is a plant extract, here standardised to seven per cent silicon; the standardisation is what makes the figure comparable at all. Vitamin C is the only component carrying an authorised claim: it contributes to normal collagen formation for the normal function of cartilage.
What does not follow from these figures
The presence of a substance does not establish an effect of the finished product. The authorised vitamin C claim refers to vitamin C, not to the combination. Research on glucosamine or MSM is not research on this product.
The only defensible statement is therefore: the product contains these substances in these amounts. Everything beyond that belongs in the sections on evidence and safety, where the limits are named.
Before you decide
Check three things before ordering: the origin of the glucosamine because of possible shellfish allergy, any medication you take because of the described interaction with coumarin anticoagulants, and the full ingredient list if you have known intolerances.
If in doubt, ask a doctor or pharmacist and show them the ingredient list. With persistent or severe joint symptoms, establishing the cause comes before any purchase decision.