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tetracycline hydrochloride
Achromycin V, Apo-Tetra†, Novo-Tetra†, Nu-Tetra†,Panmycin**, Sumycin, Sustamycin§, Tetrachel§

Pregnancy Risk Category D

How supplied
Tablets:
250 mg, 500 mg
Capsules:
100 mg, 250 mg, 500 mg
Oral suspension:
125 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-negative and gram-positive organisms (including
Haemophilus ducreyi, Yersinia pestis, and Campylobacter fetus), Rickettsia, Mycoplasma pneumoniae, and Chlamydia trachomatis; psittacosis; granuloma inguinale-
Adults:
250 to 500 mg P.O. q 6 hours.
Children over age 8:
25 to 50 mg/kg P.O. daily, in divided doses q 6 hours.
Uncomplicated urethral, endocervical, or rectal infections due to
C. trachomatis-
Adults:
500 mg P.O. q.i.d. for at least 7 days, 10 days for epididymitis, and 21 days for lymphogranuloma venereum.
Brucellosis-

Adults:
500 mg P.O. q 6 hours for 3 weeks with 1 g of streptomycin I.M. q 12 hours for first week; once daily for second week.
Gonorrhea in patients allergic to penicillin-

Adults:
initially, 1.5 g P.O.; then 500 mg q 6 hours for total dose of 9 g; for epididymitis, 500 mg P.O. q 6 hours for 7 days.
Syphilis in patients allergic to penicillin-

Adults:
total of 30 to 40 g P.O. in equally divided doses over 10 to 15 days.
Acne-

Adults and adolescents:
initially, 250 mg P.O. q 6 hours; then 125 to 500 mg daily or every other day.
Helicobacter pylori infection-
Adults:
500 mg P.O. q 6 hours for 10 to 14 days with other agents, such as metronidazole, bismuth subsalicylate, amoxicillin, or omeprazole.
Cholera-

Adults:
500 mg P.O. q 6 hours for 48 to 72 hours.
Malaria due to
Plasmodium falciparum-
Adults:
250 to 500 mg P.O. daily for 7 days with quinine sulfate 650 mg P.O. q 8 hours for 3 to 7 days.

Adverse reactions
CNS:
dizziness, headache, intracranial hypertension.
CV:
pericarditis.
EENT:
sore throat, glossitis, dysphagia.
GI:
anorexia, epigastric distress, nausea, vomiting, diarrhea, esophagitis, oral candidiasis, stomatitis, enterocolitis, inflammatory lesions in anogenital region.
GU:
increased BUN.
Hematologic:
neutropenia, eosinophilia, thrombocytopenia.
Hepatic:
elevated liver enzymes.
Musculoskeletal:
bone growth retardation in children under age 9.
Skin:
candidal superinfection, maculopapular and erythematous rash, urticaria, photosensitivity, increased pigmentation.
Other:
hypersensitivity reactions; permanent discoloration of teeth, enamel defects.

Interactions
Drug-drug.
Antacids (including sodium bicarbonate) and laxatives containing aluminum, magnesium, or calcium; antidiarrheals containing kaolin, pectin, or bismuth subsalicylate: decreased antibiotic absorption. Give antibiotic 1 hour before or 2 hours after any of these drugs.
Ferrous sulfate and other iron products, zinc:
decreased antibiotic absorption. Give tetracyclines 2 hours before or 3 hours after iron administration.
Lithium carbonate:
may alter serum lithium levels. Monitor levels.
Methoxyflurane:
may cause severe nephrotoxicity with tetracyclines. Monitor carefully.
Oral anticoagulants:
potentiated anticoagulant effects. Monitor PT and INR, and adjust anticoagulant 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-food.
Milk, dairy products, other foods: decreased antibiotic absorption. Give antibiotic 1 hour before or 2 hours after any of the above.
Drug-lifestyle.
Sun exposure: photosensitivity reactions may occur. Take precautions.

Effects on diagnostic tests
Tetracycline causes false-negative results in urine glucose tests using glucose oxidase reagent (Diastix or Chemstrip uG) and false elevations in fluorometric tests for urine catecholamines.

Contraindications
Contraindicated in patients with hypersensitivity to drug or other tetracyclines.

Nursing considerations

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

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