Glucosamine is an amino sugar and a prominent precursor in the biochemical synthesis of glycosylated proteins and lipids. Glucosamine is part of the structure of the polysaccharides chitosan and chitin, which compose the exoskeletons of crustaceans and other arthropods, as well as the cell walls of fungi and many higher organisms. Glucosamine is one of the most abundant monosaccharides. It is produced commercially by the hydrolysis of crustacean exoskeletons or, less commonly, by fermentation of a grain such as corn or wheat. Evidence for the effectiveness of glucosamine supplements is mixed. In the United States, it is one of the most common non-vitamin, non-mineral, dietary supplements used by adults. Glucosamine is marketed to support the structure and function of joints, and the marketing is targeted to people suffering from osteoarthritis. Commonly sold forms of glucosamine are glucosamine sulfate, glucosamine hydrochloride, and N-acetylglucosamine. Of the three commonly available forms of glucosamine, only glucosamine sulfate is given a "likely effective" rating for treating osteoarthritis. Glucosamine is often sold in combination with other supplements such as chondroitin sulfate and methylsulfonylmethane. Glucosamine, along with commonly used chondroitin, is not routinely prescribed to treat people who have symptomatic osteoarthritis of the knee, as there is insufficient evidence that this treatment is helpful. As is common with heavily promoted dietary supplements, the claimed benefits of glucosamine are based principally on clinical and laboratory studies. Clinical studies are divided, with some reporting relief from arthritic pain and stiffness, while higher quality studies report no benefit above placebo. There is no evidence to date that consumption of glucosamine by sport participants will prevent or limit joint damage after injury. In a randomized placebo-controlled trial, glucosamine supplementation had no additional effect on any rehabilitation outcome when given to athletes after anterior cruciate ligament (ACL) reconstruction. Glucosamine is naturally present in the shells of shellfish, animal bones, bone marrow, and fungi. D-Glucosamine is made naturally in the form of glucosamine-6-phosphate, and is the biochemical precursor of all nitrogen-containing sugars. Specifically in humans, glucosamine-6-phosphate is synthesized from fructose 6-phosphate and glutamine by glutamine—fructose-6-phosphate transaminase as the first step of the hexosamine biosynthesis pathway. The end-product of this pathway is uridine diphosphate N-acetylglucosamine (UDP-GlcNAc), which is then used for making glycosaminoglycans, proteoglycans, and glycolipids. As the formation of glucosamine-6-phosphate is the first step for the synthesis of these products, glucosamine may be important in regulating their production; however, the way that the hexosamine biosynthesis pathway is actually regulated, and whether this could be involved in contributing to human disease remains unclear.

S-Adenosylmethionine (often referred to as SAMe) is a methyl donor and a cofactor for enzyme-catalyzed methylations, including catechol O-methyltransferase (COMT) and DNA methyltransferases (DNMT). Although present in all cells, it is concentrated in liver where 85% of all methylation reactions occur. SAM is anti-apoptotic in normal hepatocytes and normal colon epithelial cells but pro-apoptotic in liver human hepatocellular carcinoma (HCC), HepG2 cells and colon cancer cells. Because of structural instability, stable salt forms of SAM are required for its use as an oral drug. The commonly used salts: tosylate, butanedisulfonate, disulfate tosylate, disulfate ditosylate, and disulfate monotosylate. SAMe has been marketed in some European countries since the mid-1980s for the treatment of depression and for other medical conditions such as osteoarthritis (joint disease that causes joint pain and stiffness), fibromyalgia (widespread pain and stiffness). In addition, it is used to treat liver disease and migraine headaches. However, it is not formally approved in the UK for the treatment of depression, and in the USA, it is classified only as a dietary supplement. Some research suggests that it is more effective than placebo in treating mild-to-moderate depression and is just as effective as antidepressant medications without the side effects (headaches, sleeplessness, and sexual dysfunction). In addition, antidepressants tend to take 6 to 8 weeks to begin working, while It seems to begin more quickly. Researchers are not sure how SAMe works to relieve depression. But they speculate it might increase the amount of serotonin in the brain just as some antidepressants do. Many studies have examined injectable forms of SAMe, not oral supplements.

Loxoprofen (INN) is a non-steroidal anti-inflammatory drug in the propionic acid derivatives group. It is marketed in Brazil, Mexico and Japan by Sankyo as its sodium salt, loxoprofen sodium, under the trade name Loxonin, Argentina as Oxeno and in India as Loxomac. It is available in these countries for oral administration, and a transdermal preparation was approved for sale in Japan on January 2006. It is usually used to treat rheumatoid arthritis and osteoarthritis. It is also used to reduce pain and inflammation after surgery, wounds and tooth removal, as well as to bring down fever or ease pain induced by acute inflammation of upper respiratory tract Loxoprofen is a prodrug. When administered orally, loxoprofen sodium hydrate is absorbed from the gastrointestinal tract as an unchanged compound with only a modest gastric-mucosal irritation. It is then rapidly biotransformed into the active metabolite trans-OH form (SRS coordination) with a potent inhibitory effect on prostaglandin biosynthesis to exert its pharmacologic effects. Inhibition of prostaglandin biosynthesis constitutes the mechanism of action of this drug, the site of action being cyclooxygenase.

Neridronic acid (6-amino-1-idroxyesilidene-1,1-bisphosphonate) is a nitrogen-containing bisphosphonate licensed in Italy for the treatment of osteogenesis imperfecta and Paget’s disease of bone. The pharmacodynamic profile is similar to that of other nitrogen-containing bisphosphonates and is characterized by its high affinity for bone tissue particularly at sites undergoing a process of remodeling. In growing children affected by osteogenesis imperfect, neridronic acid rapidly increases bone mineral density as measured by dual X-ray absorptiometry and this is associated with a significant decrease in fracture cumulative number. Similar results have been obtained also in newborns (<12-month-old) and in adult patients. In Paget’s disease of bone, 200 mg intravenous neridronic acid is associated with a 65% rate of full remission and a biochemical response (decrease of > 75% of bone turnover markers) in 95% of the patients. Neridronic acid treatment has been reported to be effective also in other skeletal diseases such as osteoporosis, algodystrophy, hypercalcemia of malignancy and bone metastasis. Neridronic acid has been developed only for parenteral use, and it is the only one used as the intramuscular injection. This avoids all the limitations of oral bisphosphonates and may be offered for a home treatment with simple nursing assistants

Feprazone is an anti-inflammatory compound developed for the treatment of such conditions as osteoarthritis, rheumatoid arthritis, rheumatic fever and gouty arthritis. The drug was tested in phase III of clinical trials, however its further faith is unknown.

Zaltoprofen is a non-steroidal anti-inflammatory drug approved in Japan for the treatment of lumbar pain, frozen shoulder, osteoarthritis, musculoskeletal pain, dental pain, post-operative pain. The main mechanism of action involves the inhibition of COX-2. Additional mechanism may be associated with the inhibitory effect of zaltoprofen on bradykinin-induced nociceptive responses that happens without blocking bradykinin receptors.

Clopirac is a non-steroidal anti-inflammatory drug. It is a weak inhibitor of prostaglandin synthetase and has standard anti-inflammatory and analgesic activity. It effectivity inhibits prostaglandin synthesis in vitro. The metabolites of clopirac in humans and monkeys include the glucuronide of clopirac and the pyrrole carboxylic acid. Efficacy of clopirac in rheumatoid arthritis, trauma conditions, osteoarthritis and pain was evaluated in many clinical trials.

Talniflumate, a prodrug of niflumic acid, is a potent analgesic and anti-inflammatory drug that has been used for the treatment of rheumatoid diseases. Talniflumate was synthesized by the esterification of a carboxyl group of niflumic acid with the phthalidyl moiety, and it exerts activity in the body through conversion to niflumic acid. Talniflumate has been studied as a mucoregulator for the treatment of cystic fibrosis, chronic obstructive pulmonary disease, and asthma. However, development of these indications appears to have been discontinued. Talniflumate has been approved and marketed for almost 20 years in Argentina and selected other countries (excluding the United States, Europe, and Japan).

Aluminum flufenamate is an anthranilic acid derivative with analgesic, anti-inflammatory, and antipyretic properties. It is used in musculoskeletal and joint disorders and administered by mouth and topically. Antiphlogistic pain reliever Opyrin (Aluminum flufenamate) was launched in Japan by Taisho Pharmaceutical in 1967.

In 2012, two newly developed active pharmaceutical ingredients for horses and food producing animals were released on the German market for veterinary drug products. Those are the parenterally applicable first generation cephalosporin Cefalonium (Cepravin) and the nonsteroidal anti-inflammatory drug Suxibuzone (Danilon). Suxibuzone is a d drug for treatment of pain and inflammation associated with musculoskeletal conditions in the horse eg. osteoarthritic conditions, bursitis, laminitis and soft tissue inflammation. It is a prodrug of the phenylbutazone, which inactivates prostaglandin H synthase and prostacyclin synthase