- Magnesium salicylate is an inorganic-organic compound composed of magnesium cations (Mg²⁺) and salicylate anions, the conjugate base of salicylic acid (C₇H₆O₃). Its general formula is commonly represented as [Mg(C₇H₅O₃)₂]·xH₂O, with the most common form being the dihydrate. This compound appears as a white, odorless, crystalline powder, and is slightly soluble in water but more soluble in alcohols and organic solvents due to the presence of aromatic rings. Magnesium salicylate is most well-known for its pharmaceutical applications as a non-steroidal anti-inflammatory drug (NSAID) and analgesic.
- In pharmaceutical contexts, magnesium salicylate is used primarily as an over-the-counter pain reliever for mild to moderate musculoskeletal pain, arthritis, and fever. It is an effective anti-inflammatory agent due to its ability to inhibit cyclooxygenase (COX) enzymes, which are responsible for the synthesis of prostaglandins—chemical mediators involved in inflammation and pain. Its pharmacological activity is similar to that of aspirin, but it is often chosen as an alternative by individuals who are sensitive to aspirin’s gastrointestinal side effects. Magnesium salicylate is frequently found in brand-name products such as Doan’s® Pills, marketed specifically for back and body pain.
- Magnesium salicylate also provides magnesium supplementation, which can be beneficial in individuals with magnesium deficiency, although this is not its primary medical use. The salicylate moiety, derived from salicylic acid, provides the therapeutic effects, while the magnesium ion may play a supporting role in buffering acidity and reducing gastrointestinal irritation compared to other salicylate salts like sodium salicylate.
- Chemically, magnesium salicylate consists of a bidentate coordination between the phenolate and carboxylate groups of salicylate and the central magnesium ion, forming a stable chelate structure. This coordination improves the compound’s stability and bioavailability. The crystalline dihydrate is relatively stable under normal conditions but should be stored in airtight containers to prevent moisture loss or uptake, which can alter its physical properties.
- Though generally regarded as safe when used at recommended dosages, magnesium salicylate, like all NSAIDs, carries potential risks. Excessive intake may lead to salicylate toxicity, with symptoms including tinnitus (ringing in the ears), dizziness, nausea, and metabolic acidosis. Individuals with renal impairment, aspirin sensitivity, bleeding disorders, or magnesium-related metabolic issues should use magnesium salicylate with caution. Long-term or high-dose use can also lead to gastrointestinal irritation, ulceration, or bleeding, though less frequently than with aspirin.
- In industrial or laboratory settings, magnesium salicylate may also serve as a buffering agent or as a ligand source in coordination chemistry studies, although such applications are rare compared to its medicinal role. It is not typically used in large-scale manufacturing or materials science.
