DEMECLOCYCLINE HYDROCHLORIDE- demeclocycline hydrochloride tablet, film coated
VersaPharm Incorporated
For Oral Use
Rx Only
To reduce the development of drug-resistant bacteria and maintain the effectiveness of demeclocycline hydrochloride tablets and other antibacterial drugs, demeclocycline hydrochloride tablets should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria.
DESCRIPTION
Demeclocycline hydrochloride is an antibiotic isolated from a mutant strain of Streptomyces aureofaciens. Chemically it is 7-Chloro-4-(dimethylamino)-1, 4, 4a, 5, 5a, 6, 11, 12a-octahydro-3, 6, 10, 12, 12a-pentahydroxy-1, 11-dioxo-2-naphthacenecarboxamide monohydrochloride.
Its structural formula is:
Chemical Structure
(click image for full-size original)
Demeclocycline Hydrochloride film coated tablet for oral administration, contains 150 mg or 300 mg of demeclocycline hydrochloride and the following inactive ingredients: Croscarmellose sodium, colloidal silicon dioxide, ethylcellulose, microcrystalline cellulose, magnesium stearate, FD&C Red #40, FD&C Yellow #6, hypromellose, polydextrose, polyethylene glycol, titanium dioxide, and triacetin.
CLINICAL PHARMACOLOGY
Pharmacokinetics
The absorption of demeclocycline is slower than that of tetracycline. The time to reach the peak concentration is about 4 hours. After a 150 mg oral dose of demeclocycline tablet, the mean concentrations at 1 hour and 3 hours are 0.46 and 1.22 ?g/mL (n=6), respectively. The serum half-life ranges between 10 and 16 hours. When demeclocycline hydrochloride is given concomitantly with some dairy products, or antacids containing aluminum, calcium, or magnesium, the extent of absorption is reduced by more than 50%. Demeclocycline hydrochloride penetrates well into various body fluids and tissues. The percent of demeclocycline hydrochloride bound to plasma protein is about 40% using a dialysis equilibrium method and 90% using an ultra-filtration method. Demeclocycline hydrochloride like other tetracyclines, is concentrated in the liver and excreted into the bile where it is found in much higher concentrations than in the blood. The rate of demeclocycline hydrochloride renal clearance (35 mL/min/1.73 m2) is less than half that of tetracycline. Following a single 150 mg dose of demeclocycline hydrochloride in normal volunteers, 44% (n = 8) was excreted in urine and 13% and 46%, respectively, were excreted in feces in two patients within 96 hours as active drug.
Microbiology
Mechanism of Action
The tetracyclines are primarily bacteriostatic and are thought to exert their antimicrobial effect by the inhibition of protein synthesis. The tetracyclines, including demeclocycline, have a similar antimicrobial spectrum of activity against a wide range of gram-negative and gram-positive organisms.
Mechanism(s) of Resistance
Resistance to tetracyclines may be mediated by efflux, alteration in the target site of tetracycline, enzymatic inactivation, and decreased bacterial permeability to the tetracycline or a combination of these mechanisms.
