Demeclocycline (DMC)

Demeclocycline is a tetracycline antibiotic derived from a strain of Streptomyces aureofaciens. Like other tetracyclines, demeclocycline is contraindicated in children and pregnant or nursing women. All members of this class interfere with bone development and may discolour teeth. These are similar to those of other tetracyclines. Skin reactions with sunlight have been reported. Demeclocycline is unique in that it is the only tetracycline known to cause nephrogenic diabetes insipidus. Tetracyclines bind to cations, such as calcium, iron (when given orally), and magnesium, rendering them insoluble and inabsorbable for the gastrointestinal tract. Demeclocycline should not be taken with food (particularly milk and other dairy products) or antacids. As with related tetracycline antibiotics, demeclocycline acts by binding to the 30S and 50S ribosomal subunits, which impairs protein synthesis by bacteria. It is bacteriostatic.