Demeclocycline Hydrochloride (demeclocycline hydrochloride 300 mg) Dailymed

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, USP 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. The structural formula is:

Each film-coated tablet, for oral administration contains 150 mg or 300 mg of demeclocycline hydrochloride, USP and has the following inactive ingredients: carnauba wax, colloidal silicon dioxide, crospovidone, hydroxypropyl cellulose, hypromelloses, magnesium stearate, microcrystalline cellulose, polydextrose, polyethylene glycol, pregelatinized starch, talc, titanium dioxide, triacetin, D&C Red No. 27 Aluminum Lake, D&C Red No. 30 Aluminum Lake, FD&C Blue No. 1 Aluminum Lake and FD&C Yellow No. 6 Aluminum Lake.

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 mcg/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

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.

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.

Cross-resistance between antibiotics of the tetracycline family occurs.

Demeclocycline has been shown to be active against most isolates of the following bacteria, in vitro and/or in clinical infections as described in the INDICATIONS AND USAGE section.

Bacillus anthracis

Listeria monocytogenes

Staphylococcus aureus

Streptococcus pneumoniae

Bartonella bacilliformis

Brucella species

Calymmatobacterum granulomatis

Campylobacter fetus

Francisella tularensis

Haemophilus ducreyi

Haemophilus influezae

Neisseria gonorrrhoeae

Vibrio cholerae

Yersinia pestis

Because many isolates of the following groups of gram-negative bacteria have been shown to be resistant to tetracyclines, culture and susceptibility testing are especially recommended:

Acinetobacter species

Enterobacter aerogenes

Escherichia coli

Klebsiella species

Shigella species

Actinomyces israelii

Borella recurrentis

Chlamydia psittaci

Chlamydia trachomatis

Clostridium species

Entamoeba species

Fusobacterium fusiforme

Mycoplasma pneumoniae

Propionibacterium acnes

Rickettsiae

Treponema pallidium subspecies pallidum

Treponema pallidum subspecies pertenue

Ureaplasma urealyticum

When available, the clinical microbiology laboratory should provide the results of in vitro susceptibility test results for antimicrobial drug products used in resident hospitals to the physician as periodic reports that describe the susceptibility profile of nosocomial and community-acquired pathogens. These reports should aid the physician in selecting an antibacterial drug product for treatment

Quantitative methods are used to determine antimicrobial minimum inhibitory concentrations (MICs). These MICs provide estimates of the susceptibility of bacteria to antimicrobial compounds. The MICs should be determined using a standardized method (broth/or agar)^1,2,3. The MIC values should be interpreted according to the criteria in Table 1.

Quantitative methods that require measurement of zone diameters can also provide reproducible estimates of the susceptibility of bacteria to antimicrobial compounds. The zone size provides an estimate of the susceptibility of bacteria to antimicrobial compounds.

The zone size should be determined using a standardized test method.^2,4 This procedure uses paper disks impregnated with 30 mcg tetracycline to test the susceptibility of microorganisms to tetracycline. The disc diffusion interpretive criteria are provided in Table 1.

Table 1. Susceptibility Test Interpretive Criteria for Tetracycline

	Minimum Inhibitory Concentration (mcg/mL)			Disk Diffusion (zone diameters in mm)
Pathogen
	S	I	R	S	I	R
Enerobacteriaceae, Acinetobacter spp.	≤4	8	>16	≥15	12 to 14	<11
Haemophilus influenzae	<2	4	>8	>29	26 to 28	<25
Neisseria gonorrhoeae	<0.25	0.5 to 1	>2	>38	31 to 37	<30
Staphylococcus aureus	≤4	8	≥16	≥19	15 to 18	≤14
S. pneumoniae (non-meningitis isolates)	≤1	2	≥4	>28	25 to 27	≤24
Bacillus anthracis	<1	--	--	--	--	--
Franciscella tularensis	<4	--	--	--	--	--

A report of Susceptible indicates that the antimicrobial is likely to inhibit growth of the pathogen if the antimicrobial compound reaches the concentrations at the infection site necessary to inhibit growth of the pathogen. A report of Intermediate indicates that the result should be considered equivocal, and, if the microorganism is not fully susceptible to alternative, clinically feasible drugs, the test should be repeated. This category implies possible clinical applicability in body sites where the drug product is physiologically concentrated or in situations where a high dosage of the drug product can be used. This category also provides a buffer zone that prevents small uncontrolled technical factors from causing major discrepancies in interpretation. A report of Resistant indicates that the antimicrobial is not likely to inhibit growth of the pathogen if the antimicrobial compound reaches the concentrations usually achievable at the infection site; other therapy should be selected.

Standardized susceptibility test procedures require the use of laboratory controls to monitor and ensure the accuracy and precision of supplies and reagents used in the assay, and the techniques of the individuals performing the test.^1,2,3,4 Standard tetracycline powder should provide the following range of MIC values noted in Table 2. For the diffusion technique using the 30 mcg tetracycline disk, the criteria in Table 2 should be achieved.

Table 2. Acceptable Quality Control Ranges for Tetracycline

*ATCC = American Type Culture Collection
QC Strain	Minimum Inhibitory Concentrations (mcg/mL)	Disk Diffusion (zone diameters in mm)
Escherichia coli ATCC* 25922	0.5 to 2	18 to 25
Staphylococcus aureus ATCC 29213	0.12 to 1	-----
Staphylococcus aureus ATCC 25923	-----	24 to 30
Haemophilus influenzae ATCC 49247	4 to 32	14 to 22
Neisseria gonorrhoeae ATCC 49226	0.25 to 1	30 to 42
Streptococcus pneumoniae ATCC 49619	0.06 to 0.5	27 to 31

Indications And Usage

Demeclocycline hydrochloride tablets USP is indicated in the treatment of infections caused by susceptible strains of the designated microorganisms in the conditions below:

Rocky Mountain spotted fever, typhus fever and the typhus group, Q fever, rickettsialpox, and tick fevers caused by rickettsiae; Respiratory tract infections caused by Mycoplasma pneumoniae; Lymphogranuloma venereum due to Chlamydia trachomatis; Psittacosis (Ornithosis) due to Chlamydia psittaci; Trachoma due to Chlamydia trachomatis, although the infectious agent is not always eliminated, as judged by immunofluorescence; Inclusion conjunctivitis caused by Chlamydia trachomatis; Nongonococcal urethritis in adults caused by Ureaplasma urealyticum or Chlamydia trachomatis; Relapsing fever due to Borrelia recurrentis;Chancroid caused by Haemophilus ducreyi;

Plague due to Yersinia pestis;

Tularemia due to Francisella tularensis;

Cholera caused by Vibrio cholerae;

Campylobacter fetus infections caused by Campylobacter fetus;

Brucellosis due to Brucella species (in conjunction with streptomycin);

Bartonellosis due to Bartonella bacilliformis;

Granuloma inguinale caused by Calymmatobacterium granulomatis;

Demeclocycline hydrochloride tablets USP is indicated for treatment of infections caused by the following gram-negative microorganisms, when bacteriologic testing indicates appropriate susceptibility to the drug:

Escherichia coli;

Enterobacter aerogenes;

Shigella species;

Acinetobacter species;

Respiratory tract infections caused by Haemophilus influenzae;

Respiratory tract and urinary tract infections caused by Klebsiella species.

Demeclocycline hydrochloride tablets USP is indicated for treatment of infections caused by the following gram-positive microorganisms, when bacteriologic testing indicates appropriate susceptibility to the drug:

Upper respiratory infections caused by Streptococcus pneumoniae;

Skin and skin structure infections caused by Staphylococcus aureus.

(Note: Tetracyclines, including demeclocycline, are not the drugs of choice in the treatment of any type of staphylococcal infection.) When penicillin is contraindicated, tetracyclines, including demeclocycline hydrochloride, are alternative drugs in the treatment of the following infections:

Uncomplicated urethritis in men due to Neisseria gonorrhoeae, and for the treatment of other uncomplicated gonococcal infections; Infections in women caused by Neisseria gonorrhoeae;

Syphilis caused by Treponema pallidum subspecies pallidum;

Yaws caused by Treponema pallidum subspecies pertenue;

Listeriosis due to Listeria monocytogenes;

Anthrax due to Bacillus anthracis;

Vincent’s infection caused by Fusobacterium fusiforme;

Actinomycosis caused by Actinomyces israelii;

Clostridial diseases caused by Clostridium species.

In acute intestinal amebiasis, demeclocycline hydrochloride tablets USP may be a useful adjunct to amebicides.

In severe acne, demeclocycline hydrochloride tablets USP may be a useful adjunctive therapy.

To reduce the development of drug-resistant bacteria and maintain the effectiveness of demeclocycline hydrochloride tablets USP and other antibacterial drugs, demeclocycline hydrochloride tablets USP should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.

Contraindications

This drug is contraindicated in persons who have shown hypersensitivity to any of the tetracyclines or any of the components of the product formulation.

Warnings

DEMECLOCYCLINE HYDROCHLORIDE, LIKE OTHER TETRACYCLINE-CLASS ANTIBIOTICS, CAN CAUSE FETAL HARM WHEN ADMINISTERED TO A PREGNANT WOMAN. IF ANY TETRACYCLINE IS USED DURING PREGNANCY, OR IF THE PATIENT BECOMES PREGNANT WHILE TAKING THESE DRUGS, THE PATIENT SHOULD BE APPRISED OF THE POTENTIAL HAZARD TO THE FETUS.

THE USE OF DRUGS OF THE TETRACYCLINE CLASS DURING TOOTH DEVELOPMENT (LAST HALF OF PREGNANCY, INFANCY AND CHILDHOOD TO THE AGE OF 8 YEARS) MAY CAUSE PERMANENT DISCOLORATION OF THE TEETH (YELLOW-GRAY-BROWN). This adverse reaction is more common during long-term use of the drugs but has been observed following repeated short-term courses. Enamel hypoplasia has also been reported. TETRACYCLINE DRUGS, THEREFORE, SHOULD NOT BE USED DURING TOOTH DEVELOPMENT UNLESS OTHER DRUGS ARE NOT LIKELY TO BE EFFECTIVE OR ARE CONTRAINDICATED.

All tetracyclines form a stable calcium complex in any bone-forming tissue. A decrease in fibula growth rate has been observed in premature human infants given oral tetracycline in doses of 25 mg/kg every six hours. This reaction was shown to be reversible when the drug was discontinued.

Results of animal studies indicate that tetracyclines cross the placenta, are found in fetal tissues, and can have toxic effects on the developing fetus (often related to retardation of skeletal development). Evidence of embryotoxicity has also been noted in animals treated early in pregnancy. The anti-anabolic action of the tetracyclines may cause an increase in BUN. While this is not a problem in those with normal renal function, in patients with significantly impaired function, higher serum levels of tetracycline may lead to azotemia, hyperphosphatemia, and acidosis.

If renal impairment exists, even usual oral or parenteral doses may lead to excessive systemic accumulation of the drug and possible liver toxicity. Under such conditions, lower than usual total doses are indicated and, if therapy is prolonged, serum level determinations of the drug may be advisable.

Photosensitivity manifested by an exaggerated sunburn reaction has been observed in some individuals taking tetracyclines. Phototoxic reactions can occur in individuals taking demeclocycline, and are characterized by severe burns or exposed surfaces resulting from direct exposure of patients to sunlight during therapy with moderate or large doses of demeclocycline. Patients apt to be exposed to direct sunlight or ultraviolet light should be advised that this reaction can occur, and treatment should be discontinued at the first evidence of erythema of the skin.

Administration of demeclocycline hydrochloride has resulted in appearance of the diabetes insipidus syndrome (polyuria, polydipsia and weakness) in some patients on long-term therapy. The syndrome has been shown to be nephrogenic, dose-dependent and reversible on discontinuance of therapy. Patients who are experiencing central nervous system symptoms associated with demeclocycline therapy should be cautioned about driving vehicles or using hazardous machinery while on demeclocycline therapy. Clostridium difficile associated with diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including demeclocycline hydrochloride, and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile.

C. difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents.

If CDAD is suspected or confirmed, ongoing antibiotic use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C. difficile, and surgical evaluation should be instituted as clinically indicated.

Precautions

General

Pseudotumor cerebri (benign intracranial hypertension) in adults has been associated with the use of tetracyclines. The usual clinical manifestations are headache and blurred vision. Bulging fontanels have been associated with the use of tetracyclines in infants. While both of these conditions and related symptoms usually resolve soon after discontinuation of the tetracycline, the possibility for permanent sequelae exists.

As with other antibiotic preparations, use of this drug may result in overgrowth of nonsusceptible organisms, including fungi. If superinfection occurs, the antibiotic should be discontinued and appropriate therapy should be instituted.

Incision and drainage or other surgical procedures should be performed in conjunction with antibiotic therapy, when indicated. Prescribing demeclocycline hydrochloride tablets in the absence of a proven or strongly suspected bacterial infection or a prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.

Information for Patients

Photosensitivity manifested by an exaggerated sunburn reaction has been observed in some individuals taking tetracyclines. Patients apt to be exposed to direct sunlight or ultraviolet light should be advised that this reaction can occur with tetracycline drugs, and treatment should be discontinued at the first evidence of skin erythema. Concurrent use of tetracyclines with oral contraceptives may render oral contraceptives less effective (see Drug Interactions ). Patients should be informed that demeclocycline hydrochloride tablets should be taken at least 1 hour before meals or 2 hours after meals (see DOSAGE AND ADMINISTRATION ). Unused supplies of tetracycline antibiotics should be discarded by the expiration date. Patients who are experiencing headache, dizziness, light-headedness, vertigo, or blurred vision while on demeclocycline therapy, should be cautioned about driving vehicles or using hazardous machinery while receiving demeclocycline therapy (see WARNINGS ).

Patients should be counseled that antibacterial drugs, including demeclocycline hydrochloride tablets should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When demeclocycline hydrochloride tablets are prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of therapy, the medication should be taken exactly as directed.

Skipping doses or not completing the full course of therapy may (1) decrease the effectiveness of the immediate treatment and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by demeclocycline hydrochloride tablets or other antibacterial drugs in the future.

Diarrhea is a common problem caused by antibiotics which usually ends when the antibiotic is discontinued. Sometimes after starting treatment with antibiotics, patients can develop watery and bloody stools (with or without stomach cramps and fever) even as late as two or more months after having taken the last dose of the antibiotic. If this occurs, patients should contact their physician as soon as possible.

Laboratory Tests

In venereal diseases when coexistent syphilis is suspected, darkfield examination should be done before treatment is started and the blood serology repeated monthly for at least 4 months. In long-term therapy, periodic laboratory evaluation of organ systems, including hematopoietic, renal, and hepatic, should be performed. All patients with gonorrhea should have a serologic test for syphilis at the time of diagnosis. Patients treated with demeclocycline hydrochloride should have a follow-up serologic test for syphilis after 3 months.

Drug Interactions

Because tetracyclines have been shown to depress plasma prothrombin activity, patients who are on anticoagulant therapy may require downward adjustment of their anticoagulant dosage. Since bacteriostatic drugs may interfere with the bactericidal action of penicillins, it is advisable to avoid giving tetracycline-class drugs in conjunction with penicillin.

Concurrent use of tetracyclines with oral contraceptives may render oral contraceptives less effective.

The concurrent use of tetracyclines and methoxyflurane has been reported to result in fatal renal toxicity.

Absorption of tetracyclines is impaired by antacids containing aluminum, calcium or magnesium, and by iron-containing preparations.

Carcinogenesis, Mutagenesis, Impairment of Fertility

Long-term studies in animals to evaluate carcinogenic potential of demeclocycline hydrochloride have not been conducted. However, there has been evidence of oncogenic activity in rats in studies with the related antibiotics oxytetracycline (adrenal and pituitary tumors) and minocycline (thyroid tumors).

Although mutagenicity studies of demeclocycline hydrochloride have not been conducted, positive results in in vitro mammalian cell assays (i.e., mouse lymphoma and Chinese hamster lung cells) have been reported for related antibiotics (tetracycline hydrochloride and oxytetracycline). (See WARNINGS; ANIMAL PHARMACOLOGY AND ANIMAL TOXICOLOGY .)

Demeclocycline hydrochloride had no effect on fertility when administered in the diet to male and female rats at a daily intake of 45 times the human dose.

Pregnancy

Pregnancy Category D

(See WARNINGS ).

Results of animal studies indicate that tetracyclines cross the placenta, are found in fetal tissues, and can have toxic effects on the developing fetus (often related to retardation of skeletal development). Evidence of embryotoxicity has been noted in animals treated early in pregnancy.

(See WARNINGS ).

Labor and Delivery

The effect of tetracyclines on labor and delivery is unknown.

Nursing Mothers

Tetracyclines are excreted in human milk. Because of the potential for serious adverse reactions in nursing infants from the tetracyclines, a decision should be made whether to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother. (See WARNINGS ).

Pediatric Use

Not for use in patients younger than eight years of age. (See WARNINGS, PRECAUTIONS, General and DOSAGE AND ADMINISTRATION .)