TETRACYCLINE-CLASS ANTIBIOTICS CAN CAUSE FETAL HARM WHEN ADMINISTERED TO A PREGNANT WOMAN. IF ANY TETRACYCLINE IS USED DURING PREGNANCY, OR IF THE PATIENT BECOMES PREGNANT WHILE TAKING THESE DRUGS, THE PATIENT SHOULD BE APPRISED OF THE POTENTIAL HAZARD TO THE FETUS.
THE USE OF DRUGS OF THE TETRACYCLINE CLASS DURING TOOTH DEVELOPMENT (LAST HALF OF PREGNANCY, INFANCY AND CHILDHOOD TO AGE OF 8 YEARS) MAY CAUSE PERMANENT DISCOLORATION OF THE TEETH (YELLOW-GRAY-BROWN).
This adverse reaction is more common during long term use of the drug but has been observed following repeated short-term courses. Enamel hypoplasia has also been reported. TETRACYCLINE DRUGS, THEREFORE, SHOULD NOT BE USED DURING TOOTH DEVELOPMENT UNLESS OTHER DRUGS ARE NOT LIKELY TO BE EFFECTIVE OR ARE CONTRAINDICATED.
All tetracyclines form a stable calcium complex in any bone forming tissues. A decrease in fibula growth rate has been observed in young animals (rats and rabbits) given oral tetracycline in doses of 25 mg/kg every six hours. This reaction was shown to be reversible when the drug was discontinued.
Results of animal studies indicate that tetracyclines cross the placenta, are found in fetal tissues and can have toxic effects on the developing fetus (often related to retardation of skeletal development). Evidence of embryotoxicity has also been noted in animals treated early in pregnancy.
Sumycin Syrup (Tetracycline Oral Suspension, USP) contains sodium metabisulfite, a sulfite that may cause allergic-type reactions including anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people. The overall prevalence of sulfite sensitivity in the general population is unknown and probably low. Sulfite sensitivity is seen more frequently in asthmatic than in nonasthmatic people.
The antianabolic action of tetracycline may cause an increase in BUN. While this is not a problem in those with normal renal function, in patients with significantly impaired function, higher serum levels of tetracycline may lead to azotemia, hyperphosphatemia, and acidosis. If renal impairment exists, even usual oral or parenteral dose may lead to excessive systemic accumulation of the drug and possible liver toxicity. Under such conditions, lower than usual doses are indicated and, if therapy is prolonged, serum level determinations of the drug may be advisable.
Photosensitivity, manifested by an exaggerated sunburn reaction, has been observed in some individuals taking tetracyclines. Patients apt to be exposed to direct sunlight or ultra-violet light should be advised that this reaction can occur with tetracycline drugs, and treatment should be discontinued at the first evidence of skin erythema. NOTE: Photosensitization reactions have occurred most frequently with demeclocycline, less with chlortetracycline, and very rarely with oxytetracycline and tetracycline.
Prescribing Sumycin Syrup (Tetracycline Oral Suspension, USP) in the absence of a 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.
As with other antibiotics, use of this drug may result in overgrowth of nonsusceptible organisms, including fungi. If superinfection occurs, the antibiotic should be discontinued and appropriate therapy instituted. NOTE: Superinfection of the bowel by staphylococci may be life-threatening. Pseudotumor cerebri (benign intracranial hypertension) in adults has been associated with the use of tetracyclines. The usual clinical manifestations are headache and blurred vision. Bulging fontanels have been associated with the use of tetracyclines in infants. While both of these conditions and related symptoms usually resolve after discontinuation of the tetracycline, the possibility for permanent sequelae exists.
Since sensitivity reactions are more likely to occur in persons with a history of allergy, asthma, hay fever, or urticaria, the preparation should be used with caution in such individuals.
Cross-sensitization among the various tetracyclines is extremely common.
Incision and drainage or other surgical procedures should be performed in conjunction with antibiotic therapy, when indicated.
Under no circumstances should outdated tetracyclines be administered, as the degradation of tetracyclines are highly nephrotoxic and have, on occasion, produced a Fanconi-like syndrome.
Information for Patients
Patients should be counseled that antibacterial drugs including Sumycin Syrup (Tetracycline Oral Suspension, USP) should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When Sumycin Syrup (Tetracycline Oral Suspension, USP) 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. Skipping doses or not completing the full course of therapy may (1) decrease the effectiveness of the immediate treatment and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by Sumycin Syrup (Tetracycline Oral Suspension, USP) or other antibacterial drugs in the future.
During long-term therapy, periodic laboratory evaluation of organ system function, including renal, hepatic, and hematopoietic systems, should be performed.
All patients with gonorrhea should have a serologic test for syphilis at the time of diagnosis. Patients treated with tetracycline should have a follow-up serologic test for syphilis after 3 months.
PENICILLIN - Since bacteriostatic drugs like tetracycline may interfere with the bactericidal action of penicillin, it is advisable to avoid giving tetracycline in conjunction with penicillin.
ANTICOAGULANTS - Because the tetracyclines have been shown to depress plasma prothrombin activity, patients who are on anticoagulant therapy may require downward adjustment of their anticoagulant dosage.
ANTACIDS AND IRON CONTAINING PRODUCTS - Absorption of tetracycline is impaired by antacids containing aluminum, calcium, or magnesium, and iron containing preparations.
ORAL CONTRACEPTIVES - Concurrent use of tetracycline may render oral contraceptives less effective.
METHOXYFLURANE - The concurrent use of tetracycline and methoxyflurane has been reported to result in fatal renal toxicity.
Carcinogenesis and Mutagenesis and Impairment of Fertility
Long-term studies conducted in rats and mice to determine whether tetracycline hydrochloride has carcinogenic potential were negative. Some related antibiotics (oxytetracycline, minocycline) have shown evidence of oncogenic activity in rats.
In two in vitro mammalian cell assay systems (L51784y mouse lymphoma and Chinese hamsterlung cells), there was evidence of mutagenicity at tetracycline hydrochloride concentrations of 60 and 10 μg/mL, respectively.
Tetracycline hydrochloride had no effect on fertility when administered in the diet to male and female rats at a daily intake of 25 times the human dose.
Pregnancy: Teratogenic effects: Pregnancy Category D (see WARNINGS.)
Pregnancy: Nonteratogenic effects: (see WARNINGS.)
Labor and Delivery
The effect of tetracyclines on labor and delivery is unknown.
Tetracyclines are present in the milk of lactating women who are taking a drug in this class. Because of the potential for serious adverse reactions in nursing infants from tetracyclines, 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 (see WARNINGS.)
See WARNINGS and DOSAGE AND ADMINISTRATION.