TETRACYCLINE HYDROCHLORIDE

(tet-ra-sye'kleen)

Novotetra

, Sumycin
Classifications: antibiotic; tetracycline;
Therapeutic: antibiotic
Pregnancy Category: D

Availability

100 mg, 125 mg, 250 mg, 500 mg capsules; 125 mg/5 mL suspension

Action

Tetracyclines usually are bacteriostatic but may be bactericidal in high concentrations. Exerts antiacne action by suppressing growth of Propionibacterium acnes within sebaceous follicles, thereby reducing free fatty acid content in sebum. Free fatty acids are thought to be largely responsible for inflammatory skin lesions (papules, pustules, cysts) and comedones of acne.

Therapeutic Effect

Effective against a variety of gram-positive and gram-negative bacteria and against most chlamydiae, mycoplasmas, rickettsiae, and certain protozoa (e.g., amebae). Exerts antiacne action by suppressing growth of Propionibacterium acnes within sebaceous follicles.

Uses

Chlamydial infections (e.g., lymphogranuloma venereum, psittacosis, trachoma, inclusion conjunctivitis, nongonococcal urethritis); mycoplasmal infections (e.g., Mycoplasma pneumoniae); rickettsial infections (e.g., Q fever, Rocky Mt spotted fever, typhus); spirochetal infections: relapsing fever (Borrelia), leptospirosis, syphilis (penicillin-hypersensitive patients); amebiases; uncommon gram-negative bacterial infections [e.g., brucellosis, shigellosis, cholera, gonorrhea (penicillin-hypersensitive patients), granuloma inguinale, tularemia]; gram-positive infections (e.g., tetanus). Also used orally and topically (solution) for inflammatory acne vulgaris; topical ointment is used for superficial skin infections. See tetracycline HCl, ophthalmic, for ophthalmic uses.

Unlabeled Uses

Actinomycosis, acute exacerbations of chronic bronchitis; Lyme disease; pericardial effusion (metastatic); acute PID; sexually transmitted epididymoorchitis; with quinine for multidrug-resistant strains of Plasmodium falciparum malaria; antiinfective prophylaxis for rape victims; recurrent cystic thyroid nodules; melioidosis; and as fluorescence test for malignancy.

Contraindications

Hypersensitivity to tetracyclines or to any ingredient in the formulation; severe renal or hepatic impairment, common bile duct obstruction; concurrent corticosteroid therapy; UV exposure. Use during tooth development [last half of pregnancy (category D)], during infancy and childhood to the 8th year. Safety of topical tetracycline preparations in children <8 y is not established.

Cautious Use

History of kidney or liver dysfunction; myasthenia gravis; history of allergy, asthma, hay fever, urticaria; undernourished patients.

Route & Dosage

Systemic Infection
Adult: PO 250–500 mg b.i.d.–q.i.d. (1–2 g/d) IM 250 mg once/d or 300 mg/d in 2–3 divided doses
Child: PO >8 y, 25–50 mg/kg/d in 2–4 divided doses IM >8 y, 15–25 mg/kg/d in 2–3 divided doses (max: 250 mg/injection)

Acne
Adult/Child: PO >8 y, 500–1000 mg/d in 4 divided doses Topical Apply to cleansed areas twice daily

Administration

Oral

Give with a full glass of water on an empty stomach at least 1 h before or 2 h after meals (food, milk, and milk products can reduce absorption by 50% or more).
Do not give immediately before bed.
Give with food if patient is having GI symptoms (e.g., nausea, vomiting, anorexia); do not give with foods high in calcium such as milk or milk products.
Shake suspension well before pouring to ensure uniform distribution of drug. Use calibrated liquid measure to dispense.
Consult physician about ordering the oral suspension formulation if patient cannot swallow pills.
Check expiration date for all tetracyclines. Fanconi-like syndrome (renal tubular dysfunction) and also an LE-like syndrome have been attributed to outdated tetracycline preparations.
Tetracycline decomposes with age, exposure to light, and when improperly stored under conditions of extreme humidity, heat, or cold. The resultant product may be toxic.
Store at 15°–30° C (59°–86° F) in tightly covered container in dry place. Protect from light.

Intramuscular

Ask patient if he or she is allergic to any of the "caine" local anesthetics. (Tetracycline for IM use contains 40 mg procaine HCl per vial.)
Reconstitute powder by adding 2 mL sterile water for injection or NS injection to 100- or 250-mg vial.
Give injection deep into body of a relatively large muscle mass (e.g., gluteus maximus or midlateral thigh). Alternate injection sites and observe daily for irritation and swelling.
Forewarn patient that IM administration may cause local irritation and is extremely painful.
Store solution at room temperature. Discard after 24 h (directions may vary with manufacturer).

Adverse Effects (≥1%)

CNS: Headache, intracranial hypertension (rare). Special Senses: Pigmentation of conjunctiva due to drug deposit. GI: Reported mostly for oral administration, but also may occur with parenteral tetracycline (nausea, vomiting, epigastric distress, heartburn, diarrhea, bulky loose stools, steatorrhea, abdominal discomfort, flatulence, dry mouth); dysphagia, retrosternal pain, esophagitis, esophageal ulceration with oral administration, abnormally high liver function test values, decrease in serum cholesterol, fatty degeneration of liver [jaundice, increasing nitrogen retention (azotemia), hyperphosphatemia, acidosis, irreversible shock]; foul-smelling stools or vaginal discharge, stomatitis, glossitis; black hairy tongue (lingua nigra), diarrhea: staphylococcal enterocolitis. Body as a Whole: Drug fever, angioedema, serum sickness, anaphylaxis. Urogenital: Particularly in patients with kidney disease; increase in BUN/serum creatinine, renal impairment even with therapeutic doses; Fanconi-like syndrome (outdated tetracycline) (characterized by polyuria, polydipsia, nausea, vomiting, glycosuria, proteinuria acidosis, aminoaciduria); vulvovaginitis, pruritus vulvae or ani (possibly hypersensitivity). Skin: Dermatitis, phototoxicity: discoloration of nails, onycholysis (loosening of nails); cheilosis; fixed drug eruptions particularly on genitalia; thrombocytopenic purpura; urticaria, rash, exfoliative dermatitis; with topical applications: skin irritation, dry scaly skin, transient stinging or burning sensation, slight yellowing of skin at application site, acute contact dermatitis. Other: Pancreatitis, local reactions: pain and irritation (IM site), Jarisch-Herxheimer reaction (see Nursing Implications).

Diagnostic Test Interference

tetracyclines may cause false increases in urinary catecholamines (by fluorometric methods), and false decreases in urinary urobilinogen. Parenteral tetracyclines containing ascorbic acid reportedly may produce false-positive urinary glucose determinations by copper reduction methods (e.g., Benedict's reagent, Clinitest); tetracyclines may cause false-negative results with glucose oxidase methods (e.g., Clinistix, TesTape).

Interactions

Drug: antacids, calcium, and magnesium bind tetracycline in gut and decrease absorption. oral anticoagulants potentiate hypoprothrombinemia. antidiarrheal agents with kaolin and pectin may decrease absorption. Effectiveness of oral contraceptives decreased. Methoxyflurane may produce fatal nephrotoxicity. Food: Dairy products and iron, zinc supplements decrease tetracycline absorption.

Pharmacokinetics

Absorption: 75–80% of dose absorbed. Peak: 2–4 h. Distribution: Widely distributed, preferentially binds to rapid growing tissues; crosses placenta; enters breast milk. Metabolism: Not metabolized; enterohepatic cycling. Elimination: 50–60% in urine within 72 h. Half-Life: 6–12 h.

Nursing Implications

Assessment & Drug Effects

Lab tests: Obtain baseline and periodic C&S tests to confirm susceptibility of infecting organism to tetracycline. Also, preform initial and periodic kidney, liver, and hematopoietic function tests, particularly during high-dose, long-term therapy. Determine serum tetracycline levels in patients at-risk for hepatotoxicity (sometimes associated with pancreatitis and occurs most frequently in patients receiving other hepatotoxic drugs or with history of renal or hepatic impairment).
Report GI symptoms (e.g., nausea, vomiting, diarrhea) to physician. These are generally dose-dependent, occurring mostly with oral forms in patients receiving 2 g/d or more and during prolonged therapy. Frequently, symptoms are controlled by reducing dosage or administering with compatible foods.
Be alert to evidence of superinfections (see Appendix F). Regularly inspect tongue and mucous membrane of mouth for candidiasis (thrush). Suspect superinfection if patient complains of irritation or soreness of mouth, tongue, throat, vagina, or anus, or persistent itching of any area, diarrhea, or foul-smelling excreta or discharge.
Withhold drug and notify physician if superinfection develops. Superinfections occur most frequently in patients receiving prolonged therapy, the debilitated, or those who have diabetes, leukemia, systemic LE, or lymphoma. Women taking oral contraceptives reportedly are more susceptible to vaginal candidiasis.
Obtain follow-up cultures from all gonococcal infection sites 3–7 d after completion of tetracycline therapy to verify eradication of infection.
Monitor I&O in patients receiving parenteral tetracycline. Report oliguria or any changes in appearance of urine or in I&O.

Patient & Family Education

Report onset of diarrhea to physician. It is important to determine whether diarrhea is due to irritating drug effect or superinfections or pseudomembranous colitis (caused by overgrowth of toxin-producing bacteria: Clostridium difficile) (see Appendix F). The latter two conditions can be LIFE THREATENING and require immediate withdrawal of tetracycline and prompt initiation of symptomatic and supportive therapy.
Reduce incidence of superinfection (see Appendix F) by meticulous care of mouth, skin, and perineal area. Rinse mouth of food debris after eating; floss daily and use a soft-bristled toothbrush. Wash hands several times a day, particularly after each bowel movement and before eating.
Avoid direct exposure to sunlight during and for several days after therapy is terminated to reduce possibility of photosensitivity reaction (appearing like an exaggerated sunburn, it begins a few minutes to hours following sun exposure, often with tingling, burning sensation).
Report onset of severe headache or visual disturbances immediately. These are possible symptoms of increased intracranial pressure and necessitate prompt withdrawal of tetracycline to prevent irreversible loss of vision.
Note: Tetracycline therapy for brucellosis or spirochetal infections may cause a Jarisch-Herxheimer reaction. The reaction is usually mild and appears abruptly within 6–24 h after initiation of therapy. It is manifested by malaise, fever, chills, headache, adenopathy, leukocytosis, exacerbation of skin lesions, arthralgia, transient hypotension. Treatment is symptomatic; recovery generally occurs within 24 h.
Report immediately sudden onset of painful or difficult swallowing (dysphagia) to physician. Esophagitis and esophageal ulceration have been associated with bedtime administration of tetracycline capsules or tablets with insufficient fluid, particularly to patients with hiatal hernia or esophageal problems.
Do not allow topical medication to contact eyes, nose, or mouth. Be aware that tetracycline may stain clothing.
Clean affected skin area with soap and water; rinse and dry well before application of topical drug.
Report a worsening infection or stinging and burning sensation with topical applications to physician if pronounced.
Skin treated with topical drug will exhibit bright yellow to green fluorescence under ultraviolet light and "black light."
Be aware that topicycline contains a sulfite that can cause an allergic reaction (itching, wheezing, anaphylaxis) in susceptible persons (e.g., asthmatics or allergic individuals).
Response to acne therapy usually requires 2–8 wk, maximal results may not be apparent for up to 12 wk.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug

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