doxycycline hyclate
doxycycline hydrochloride
doxycycline monohydrate
Pregnancy Risk Category D
How supplied
doxycycline calcium
Oral suspension: 50 mg/5 ml
doxycycline hyclate
Tablets (film-coated): 100 mg
Capsules: 50 mg, 100 mg
Capsules (enteric-coated pellets): 100 mg
Injection: 100 mg, 200 mg
doxycycline hydrochloride
Tablets: 50 mg‡, 100 mg‡
Capsules: 50 mg‡, 100 mg‡
doxycycline monohydrate
Capsules: 50 mg, 100 mg
Oral suspension: 25 mg/5 ml
Action
Unknown. Thought to exert bacteriostatic effect by binding to the 30S and possibly 50S ribosomal subunits of microorganisms, thus inhibiting protein synthesis. May also alter the cytoplasmic membrane of susceptible microorganisms.
Indications & dosage
Infections due to susceptible gram-positive and gram-negative organisms (including Haemophilus ducreyi, Yersinia pestis, and Campylobacter fetus), Rickettsiae, Mycoplasma pneumoniae, Chlamydia trachomatis, and Borrelia burgdorferi (Lyme disease); psittacosis; granuloma inguinale-
Adults and children over age 8 weighing at least 45 kg (99 lb): 100 mg P.O. q 12 hours on first day; then 100 mg P.O. daily. Or, 200 mg I.V. on first day in one or two infusions; then 100 to 200 mg I.V. daily.
Children over age 8 and under 45 kg: 4.4 mg/kg P.O. or I.V. daily, in divided doses q 12 hours on first day; then 2.2 to 4.4 mg/kg daily in one or two divided doses.
Give I.V. infusion slowly (minimum 1 hour). Infusion must be completed within 12 hours (within 6 hours in lactated Ringer's solution or dextrose 5% in lactated Ringer's solution).
Gonorrhea in patients allergic to penicillin-
Adults: 100 mg P.O. b.i.d. for 7 days (10 days for epididymitis).
Primary or secondary syphilis in patients allergic to penicillin-
Adults: 300 mg P.O. daily in divided doses for at least 10 days.
Uncomplicated urethral, endocervical, or rectal infections due to C. trachomatis or Ureaplasma urealyticum-
Adults: 100 mg P.O. b.i.d. for at least 7 days (10 days for epididymitis).
Prophylaxis of malaria-
Adults: 100 mg P.O. daily.
Children over age 8: 2 mg/kg P.O. once daily. Dose shouldn't exceed that of adults.
Note: Prophylaxis should begin 1 to 2 days before travel to endemic area and continued until 4 weeks after travel.
Pelvic inflammatory disease-
Adults: 100 mg I.V. q 12 hours with cefoxitin or cefotetan and continued for at least 2 days after symptomatic improvement; thereafter, 100 mg P.O. q 12 hours for a total course of 14 days.
Adverse reactions
CNS: intracranial hypertension.
CV: pericarditis, thrombophlebitis.
EENT: glossitis, dysphagia.
GI: anorexia, epigastric distress, nausea, vomiting, diarrhea, oral candidiasis, enterocolitis, anogenital inflammation.
Hematologic: neutropenia, eosinophilia, thrombocytopenia, hemolytic anemia.
Hepatic: elevated liver enzymes.
Musculoskeletal: bone growth retardation in children under age 9.
Skin: maculopapular and erythematous rashes, photosensitivity, increased pigmentation, urticaria.
Other: hypersensitivity reactions, anaphylaxis, superinfection; permanent discoloration of teeth, enamel defects.
Interactions
Drug-drug. Antacids (including sodium bicarbonate) and laxatives containing aluminum, magnesium, or calcium; antidiarrheals: decreased antibiotic absorption. Give antibiotic 1 hour before or 2 hours after any of these drugs.
Carbamazepine, phenobarbital: decreased antibiotic effect. Avoid if possible.
Ferrous sulfate and other iron products, zinc: decreased antibiotic absorption. Give drug 2 hours before or 3 hours after iron administration.
Methoxyflurane: may cause nephrotoxicity with tetracyclines. Monitor carefully.
Oral anticoagulants: increased anticoagulant effect. Monitor PT and INR, and adjust dosage as ordered.
Oral contraceptives: decreased contraceptive effectiveness and increased risk of breakthrough bleeding. Use a nonhormonal form of birth control.
Penicillins: may interfere with bactericidal action of penicillins. Avoid use together.
Drug-lifestyle. Alcohol use: decreased antibiotic effect. Avoid use together.
Sun exposure: photosensitivity reactions may occur. Take precautions.
Effects on diagnostic tests
Drug causes false-negative results in urine glucose tests using glucose oxidase reagent (Diastix or Chemstrip uG). Parenteral dosage form may cause false-positive Clinitest results. Drug also causes false elevations in fluorometric tests for urine catecholamines.
Contraindications
Contraindicated in patients with hypersensitivity to drug or other tetracyclines.
Nursing considerations
I.V. administration
Patient teaching
*Liquid contains alcohol. **May contain tartrazine. †Canada ‡Australia §U.K. OTCOver the counter
Reactions may be common, uncommon, life-threatening, or COMMON AND LIFE-THREATENING