Doxycycline

What is Doxycycline?

• Doxycycline broad-spectrum antibacterial synthetically derived from oxytetracycline used to treat a variety of infections caused by certain types of bacteria.

Doxycycline structure

Doxycycline 3D ball

Doxycycline chemical structure

What are the uses of this medicine?

Doxycycline is used for the treatment of the following infections:

• Rocky mountain spotted fever, typhus fever and the typhus group, Q fever, rickettsial pox, and tick fevers caused by Rickettsiae.
• Respiratory tract infections caused by Mycoplasma pneumoniae.
• Lymphogranuloma venereum caused by Chlamydia trachomatis.
• Psittacosis (ornithosis) caused by Chlamydophila psittaci.
• Trachoma caused by Chlamydia trachomatis, although the infectious agent is not always eliminated as judged by immunofluorescence.
• Inclusion conjunctivitis caused by Chlamydia trachomatis.
• Uncomplicated urethral, endocervical or rectal infections in adults caused by Chlamydia trachomatis.
• Nongonococcal urethritis caused by Ureaplasma urealyticum.
• Relapsing fever due to Borrelia recurrentis.

Doxycycline is also indicated for the treatment of infections caused by the following gram-negative microorganisms:

• 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 Klebsiella granulomatis.
• 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.

Doxycycline 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.
• Anthrax due to Bacillus anthracis, including inhalational anthrax (post-exposure); to reduce the incidence or progression of disease following exposure to aerosolized Bacillus anthracis.

When penicillin is contraindicated, doxycycline is an alternative drug in the treatment of the following infections:

• Uncomplicated gonorrhea caused by Neisseria gonorrhoeae.
• Syphilis caused by Treponema pallidum.
• Yaws caused by Treponema pallidum subspecies pertenue.
• Listeriosis due to Listeria monocytogenes.
• Vincent’s infection caused by Fusobacterium fusiforme.
• Actinomycosis caused by Actinomyces israelii.
• Infections caused by Clostridium species.

In acute intestinal amebiasis, doxycycline may be a useful adjunct to amebicides.

• In severe acne, doxycycline may be useful adjunctive therapy.

• Doxycycline may also be used for the treatment of malaria.
• It may also be used to treat Lyme disease or to prevent Lyme disease in certain people who have been bitten by a tick.
• It may also be used to prevent infection in people who were sexually attacked.

How does this medicine work?

• Doxycycline (dox" i sye' kleen) is a semisynthetic [[tetracycline that is used for mild-to-moderate infections due to susceptible organisms. Doxycycline, like other tetracyclines, is active against a wide spectrum of gram-positive and gram-negative bacteria as well as against several rickettsia, spirochetes, chlamydia and mycoplasma.
• Doxycycline inhibits bacterial protein synthesis by binding to the 30S ribosomal subunit.
• Doxycycline has bacteriostatic activity against a broad range of Gram-positive and Gram-negative bacteria.

Who Should Not Use this medicine ?

This medicine cannot be used in patients who:

• have shown hypersensitivity to any of the tetracyclines.

What drug interactions can this medicine cause?

Tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following:

• acitretin
• anticoagulants ('blood thinners') such as warfarin (Jantoven)
• bismuth subsalicylate
• carbamazepine (Epitol, Tegretol, others)
• isotretinoin (Absorica, Clavaris, Myorisan, Zenatane)
• penicillin
• phenobarbital
• phenytoin (Phenytek)
• and proton pump inhibitors such as dexlansoprazole (Dexilant), esomeprazole (Nexium, in Vimovo), lansoprazole (Prevacid), omeprazole (Prilosec, Zegerid, in Talicia), pantoprazole (Protonix), and rabeprazole (Aciphex).

Is this medicine FDA approved?

• Doxycycline was approved for use in the United States in 1967 and is still widely used, with more than 11 million prescriptions filled yearly.

How should this medicine be used?

Recommended dosage: In Adults:

• The usual dose of oral doxycycline is 200 mg on the first day of treatment (administered 100 mg every 12 hours or 50 mg every 6 hours) followed by a maintenance dose of 100 mg/day.
• The maintenance dose may be administered as a single dose or as 50 mg every 12 hours.
• In the management of more severe infections (particularly chronic infections of the urinary tract), 100 mg every 12 hours is recommended.

In Pediatric Patients:

• For all pediatric patients weighing less than 45 kg with severe or life-threatening infections (e.g. anthrax, Rocky Mountain spotted fever), the recommended dosage is 2.2 mg/kg of body weight administered every 12 hours.
• Children weighing 45 kg or more should receive the adult dose.

Uncomplicated gonococcal infections in adults (except anorectal infections in men):

• 100 mg, by mouth, twice a day for 7 days.
• As an alternate single visit dose, administer 300 mg stat followed in one hour by a second 300 mg dose.

Acute epididymo-orchitis caused by N. gonorrhoeae:

• 100 mg, by mouth, twice a day for at least 10 days.

Primary and secondary syphilis:

• 300 mg a day in divided doses for at least 10 days.

Uncomplicated urethral, endocervical, or rectal infection in adults caused by Chlamydia trachomatis:

• 100 mg, by mouth, twice a day for at least 7 days.

Nongonococcal urethritis caused by C. trachomatis and U. urealyticum:

• 100 mg, by mouth, twice a day for at least 7 days.

Acute epididymo-orchitis caused by C. trachomatis:

• 100 mg, by mouth, twice a day for at least 10 days.

Inhalational anthrax (post-exposure):

• Adults: 100 mg of doxycycline, by mouth, twice a day for 60 days.
• Children: weighing less than 45 kg 2.2 mg/kg of body weight, by mouth, twice a day for 60 days. Children weighing 45 kg or more should receive the adult dose.

Administration:

• Doxycycline comes as a capsule, tablet, delayed-release tablet, and suspension (liquid) to take by mouth.
• Doxycycline is usually taken once or twice a day.
• Drink a full glass of water with each dose.
• If your stomach becomes upset when you take doxycycline, you may take it with food or milk.
• Swallow the delayed-release tablets whole; do not split, chew, or crush them.
• If you cannot swallow certain delayed-release tablets (Doryx; generics) whole, carefully break up the tablet and sprinkle the contents of the tablet on a spoonful of cold or room temperature (not hot) applesauce. Be careful not to crush or damage any of the pellets while you are breaking up the tablet. Eat the mixture right away and swallow without chewing. If the mixture cannot be eaten right away it should be discarded.
• Shake the suspension well before each use to mix the medication evenly.
• One doxycycline product may not be able to be substituted for another.
• If you are taking doxycycline for the prevention of malaria, start taking it 1 or 2 days before traveling to an area where there is malaria.
• Continue taking doxycycline each day you are in the area, and for 4 weeks after leaving the area.
• You should not take doxycycline for the prevention of malaria for more than 4 months.

What are the dosage forms and brand names of this medicine?

This medicine is available in fallowing doasage form:

• As a capsule, tablet, delayed-release tablet, and suspension (liquid)

This medicine is available in fallowing brand namesː

• Acticlate
• Acticlate CAP
• Doryx
• Doryx MPC
• Doxychel
• Monodox
• Oracea
• Periostat
• Vibra-Tabs
• Vibramycin

What side effects can this medication cause?

The most common side effects of this medicine include: Gastrointestinal related:

• Anorexia, nausea, vomiting, diarrhea, glossitis, dysphagia, enterocolitis, and inflammatory lesions (with monilial overgrowth) in the anogenital region, pancreatitis, Hepatotoxicity

Skin related: Maculopapular and erythematous rashes, Stevens-Johnson syndrome, toxic epidermal necrolysis, and erythema multiforme

Hypersensitivity Reactions:

• Urticaria, angioneurotic edema, anaphylaxis, anaphylactoid purpura, serum sickness, pericarditis, and exacerbation of systemic lupus erythematosus.

Blood related:

• Hemolytic anemia, thrombocytopenia, neutropenia, and eosinophilia

What special precautions should I follow?

• Tetracyclines are excreted in human milk. Because of the potential for adverse reactions in nursing infants from doxycycline, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.
• Avoid excessive sunlight or artificial ultraviolet light while receiving doxycycline and to discontinue therapy if phototoxicity (e.g., skin eruption, etc.) occurs. Sunscreen or sunblock should be considered.
• Drink fluids liberally along with doxycycline to reduce the risk of esophageal irritation and ulceration.
• Absorption of tetracyclines is reduced when taken with foods, especially those which contain calcium. However, the absorption of doxycycline is not markedly influenced by simultaneous ingestion of food or milk.
• The absorption of tetracyclines is reduced when taking bismuth subsalicylate.
• The use of doxycycline might increase the incidence of vaginal candidiasis.
• Patients should be counseled that antibacterial drugs, including doxycycline should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When doxycycline is 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.
• Diarrhea is a common problem caused by antibacterial drugs, which usually ends when the antibacterials are discontinued.
• As with other antibacterial drugs, use of doxycycline may result in overgrowth of nonsusceptible organisms, including fungi. If superinfection occurs, doxycycline should be discontinued and appropriate therapy instituted.
• Prescribing doxycycline in the absence of 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.
• Severe skin reactions, such as exfoliative dermatitis, erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis, and drug reaction with eosinophilia and systemic symptoms (DRESS) have been reported in patients receiving doxycycline. If severe skin reactions occur, doxycycline should be discontinued immediately and appropriate therapy should be instituted.
• Intracranial hypertension (IH, pseudotumor cerebri) has been associated with the use of tetracyclines including doxycycline. Concomitant use of isotretinoin and doxycycline should be avoided.

Patients taking doxycycline for malaria prophylaxis should be advised:

• that no present-day antimalarial agent, including doxycycline, guarantees protection against malaria.
• to avoid being bitten by mosquitoes by using personal protective measures that help avoid contact with mosquitoes, especially from dusk to dawn (e.g., staying in well-screened areas, using mosquito nets, covering the body with clothing, and using an effective insect repellent).
• that doxycycline prophylaxis:
• should begin 1-2 days before travel to the malarious area,
• should be continued daily while in the malarious area and after leaving the malarious area,
• should be continued for 4 further weeks to avoid development of malaria after returning from an endemic area,
• should not exceed 4 months.

• Doxycycline is a semisynthetic, tetracycline related bacteriostatic antibiotic that has been linked to rare instances of acute cholestatic liver injury.

What to do in case of emergency/overdose?

• In case of overdose, call the poison control helpline of your country. In the United States, call 1-800-222-1222.

• Overdose related information is also available online at poisonhelp.org/help.
• In the event that the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services. In the United States, call 911.

Can this medicine be used in pregnancy?

• Pregnancy Category D
• There are no adequate and well-controlled studies on the use of doxycycline in pregnant short-term, first trimester exposure.

Can this medicine be used in children?

• Because of the effects of drugs of the tetracycline-class, on tooth development and growth, use doxycycline in pediatric patients 8 years of age or less only when the potential benefits are expected to outweigh the risks in severe or life-threatening conditions.

What are the active and inactive ingredients in this medicine?

Active ingredient:

• doxycycline

Inactive ingredients:

• silicon dioxide
• gelatin, unspecified
• magnesium stearate
• microcrystalline cellulose
• sodium starch glycolate type a potato
• titanium dioxide
• ferrosoferric oxide
• ferric oxide red
• ferric oxide yellow

Who manufactures and distributes this medicine?

Capsules: Manufactured by:

• Chartwell Pharmaceuticals, LLC.
• Congers, NY

Manufactured for:

• Chartwell RX, LLC.
• Congers, NY

What should I know about storage and disposal of this medication?

• Dispense in a tight, light-resistant container as defined in the USP.
• Use child-resistant closure (as required).
• Store at 20° to 25° C (68° to 77° F).

List of tetracyclines

• Demeclocycline
• Doxycycline
• Minocycline
• Tetracycline
• Tigecycline

• Dailymed label info on Doxycycline
• FDA Doxycycline

Doxycycline Resources
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