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trademark for preparations of tetracycline hydrochloride, an antibiotic.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


(te-tra-sye-kleen) ,


(trade name)


Therapeutic: anti infectives
Pharmacologic: tetracyclines
Pregnancy Category: D


Treatment of various infections due to unusual organisms, including::
  • Mycoplasma,
  • Chlamydia,
  • Rickettsia,
  • Borrelia burgorferi.
Treatment of gonorrhea and syphilis in penicillin-allergic patients.Prevention of exacerbations of chronic bronchitis.Treatment of acne.


Inhibits bacterial protein synthesis at the level of the 30S bacterial ribosome.

Therapeutic effects

Bacteriostatic action against susceptible bacteria.
Includes activity against some gram-positive pathogens::
  • Bacillus anthracis,
  • Clostridium perfringens,
  • Clostridium tetani,
  • Listeria monocytogenes,
  • Nocardia,
  • Propionibacterium acnes,
  • Actinomyces israelii.
Active against some gram-negative pathogens::
  • Haemophilus influenzae,
  • Legionella pneumophila,
  • Yersinia entercolitica,
  • Yersinia pestis,
  • Neisseria gonorrhoeae,
  • Neisseria meningitidis.
Also active against several other pathogens, including::
  • Mycoplasma,
  • Treponema pallidum,
  • Chlamydia,
  • Rickettsia,
  • B. burgdorferi.


Absorption: 60–80% absorbed after oral administration.
Distribution: Widely distributed, some CSF and good bone penetration; crosses the placenta and enters breast milk.
Metabolism and Excretion: Excreted mostly unchanged by the kidneys.
Half-life: 6–12 hr.

Time/action profile (blood levels)

PO1–2 hr2–4 hr6–12 hr


Contraindicated in: Hypersensitivity; Some products contain alcohol or bisulfites and should be avoided in patients with known hypersensitivity or intolerance; Pediatric: Children <8 yr (permanent staining of teeth); Obstetric: Risk of permanent staining of teeth in infant if used during last half of pregnancy; Lactation: Lactation.
Use Cautiously in: Cachectic or debilitated patients; Renal disease; Nephrogenic diabetes insipidus.

Adverse Reactions/Side Effects

Central nervous system

  • benign intracranial hypertension (↑ in children)
  • dizziness


  • diarrhea (most frequent)
  • nausea (most frequent)
  • vomiting (most frequent)
  • esophagitis
  • hepatotoxicity
  • pancreatitis


  • photosensitivity (most frequent)
  • rashes


  • blood dyscrasias


  • hypersensitivity reactions
  • superinfection


Drug-Drug interaction

May ↑ the effect of warfarin.May ↓ effectiveness of estrogen-containing oral contraceptives.Antacids,calcium, iron, and magnesium form insoluble compounds (chelates) and ↓ absorption of tetracycline.Sucralfate may bind to tetracycline and prevent its absorption from the GI tract.Cholestyramine orcolestipol ↓ absorption.Adsorbentantidiarrheal agents may ↓ absorption.Barbiturates, phenytoin, orcarbamazepine may ↓ activity of doxycycline.Calcium in foods or dairy products ↓ absorption by forming insoluble compounds (chelates).


Oral (Adults) 250–500 mg q 6 hr or 500 mg–1 g q 12 hr. Chronic treatment of acne—500 mg–2 g/day for 3 wk, then ↓ to 125 mg–1 g/day.
Oral (Children ≥8 yr) 6.25–12.5 mg/kg q 6 hr or 12.5–25 mg/kg q 12 hr.

Availability (generic available)

Capsules: 250 mg, 500 mg
In combination with: bismuth subsalicylate tablets and metronidazole tablets (Helidac) as part of a compliance package; bismuth subcitrate potassium and metronidazole (Pylera). See combination drugs.

Nursing implications

Nursing assessment

  • Infection: Assess for infection (vital signs; appearance of wound, sputum, urine, and stool; WBC) at beginning of and throughout therapy.
    • Obtain specimens for culture and sensitivity before initiating therapy. First dose may be given before receiving results.
  • Lab Test Considerations: Renal and hepatic functions and CBC should be monitored periodically during long-term therapy.
    • May cause ↑ AST, ALT, serum alkaline phosphatase, bilirubin, and amylase concentrations. Tetracyclines, except doxycycline, may cause elevated serum BUN.
    • May cause false ↑ in urinary catecholamine levels.

Potential Nursing Diagnoses

Risk for infection (Indications,  Side Effects)
Deficient knowledge, related to medication regimen (Patient/Family Teaching)
Noncompliance (Patient/Family Teaching)


  • May cause yellow-brown discoloration and softening of teeth and bones if administered prenatally or during early childhood. Not recommended for children <8 yr of age or during pregnancy or lactation.
  • Oral: Administer around the clock. Administer at least 1 hr before or 2 hr after meals. Administer with a full glass of liquid at least 1 hr before going to bed to avoid esophageal ulceration.
    • Avoid administration of calcium, antacids, magnesium-containing medications, sodium bicarbonate, or iron supplements within 1–3 hr of tetracycline.

Patient/Family Teaching

  • Instruct patient to take medication around the clock and to finish the drug completely, as directed, even if feeling better. If a dose is missed, take as soon as possible unless almost time for next dose; do not double doses. Advise patient that sharing of this medication may be dangerous.
    • Advise patient to avoid taking milk or other dairy products concurrently with tetracycline. Also avoid taking antacids, calcium, magnesium-containing medications, sodium bicarbonate, and iron supplements within 1–3 hr of tetracycline.
    • Caution patient to use sunscreen and protective clothing to prevent photosensitivity reactions.
    • Advise patient to report the signs of superinfection (black, furry overgrowth on the tongue; vaginal itching or discharge; loose or foul-smelling stools). Skin rash, pruritus, and urticaria should also be reported.
    • Instruct patient to notify health care professional of medication regimen before treatment or surgery.
    • Advise female patients to use a nonhormonal method of contraception while taking tetracycline and until next menstrual period.
    • Instruct patient to notify health care professional if symptoms do not improve within a few days for systemic preparations.
    • Caution patient to discard outdated or decomposed tetracycline; may be toxic.

Evaluation/Desired Outcomes

  • Resolution of the signs and symptoms of infection. Length of time for complete resolution depends on the organism and site of infection.
  • Decrease in acne lesions.
Drug Guide, © 2015 Farlex and Partners