Lithium acetylsalicylate

Calcium acetylsalicylate, Ci8Hi403Ca,2H20, Mol. Wt. 434 4, and lithium acetylsalicylate, CgH704Li, Mol. Wt. 186 1, are estimated by weighing their sulphated ash. Caution is necessary when sulphuric acid is added to the ash for sulphating. 1 g CaS04 = 3-191 g calcium aspirin and 1 g Li2S04 --- 3 385 g lithium aspirin. 

Acetylsalicylic acid is usually given by oral administration (0.5-8 g/day) for pain and inflammation and for antiplatelet therapy (75-100 mg/day). It is also available in rectal and topical formulations and as a soluble lysine derivative for intravenous or intramuscular application. Acetylsalicylic acid is often used in multi-drug preparations. The main side-effects are gastrointestinal disorders. Use in children is limited due to the risk of Reye s syndrome (Waldmann et al., 1982). The lithium, magnesium, calcium, and aluminium salts of acetylsalicylic acid are used in some special preparations. 

Among the drugs that can be managed in this way are the weak acids phenobarbital and acetylsalicylic acid, the weak bases phencyclidine and amphetamine, and the ion lithium. 

Various NSAIDs, such as ibuprofen, indomethacin, ketoprofen, phenylbutazone, piroxicam, and oxyphenbutazone, can decrease renal creatinine and lithium clearance by their common inhibitory action on prostaglandin synthesis. Aspirin (acetylsalicylic acid) and sulindac have not been found to increase lithium plasma steady-state concentrations. ... 

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