Tetracyclines adverse reactions

Discuss ways to promote an optimal response to therapy, how to manage adverse reactions, and important points to keep in mind when educating patients about the use of a tetracycline, macrolide, or lincosamide. 

Discuss the uses, general drug action, adverse reactions, contraindications, precautions, and interactions of the tetracyclines, macrolides, and... 

Doxycycline (Vibramycin) is an antibiotic belonging to die tetracycline group of antibiotics. The adverse reactions associated with this drug are discussed in Chapter 9 and include photosensitivity, anorexia, nausea, and vomiting. 

The following adverse reactions have been reported with the tetracyclines. 

Glycylcycline class antibiotics are structurally similar to tetracycline class antibiotics and may have similar adverse reactions. 

EC chewable solution oral 10 mg/ml Videx EC 125 mg 200 mg 250 mg 400 mg capsules tetracyclines, oral quinolones, ganciclovir Adverse reaction optic neuritis... 

Adverse reactions. Heartburn, nausea and vomiting due to gastric irritation are common, and attempts to reduce this with milk or antacids impair absorption of tetracyclines (see below). Loose bowel movements occur, due to alteration of the bowel flora, and this sometimes develops into diarrhoea and opportunistic infection (antibiotic associated or pseudomembranous colitis) may supervene. Disorders of epithelial surfaces, perhaps due partly to vitamin B complex deficiency and partly due to mild opportunistic infection with yeasts and moulds, lead to sore mouth and throat, black hairy tongue, dysphagia and perianal soreness. Vitamin B preparations may prevent or arrest alimentary tract symptoms. 

Adverse reactions. Erythromycin is remarkably nontoxic, but the estolate can cause cholestatic hepatitis with abdominal pain and fever which may be confused with viral hepatitis, acute cholecystitis or acute pancreatitis. This is probably an allergy, and recovery is usual but the estolate should not be given to a patient with liver disease. Other allergies are rare. Gastrointestinal disturbances occur frequently (up to 28%), particularly diarrhoea and nausea, but, with the antibacterial spectrum being narrower than with tetracycline, opportunistic infection is less troublesome. 

Adverse effects of minocycline are reported far more often than adverse effects of other tetracycline derivatives. Whatever the mechanisms underlying this larger number of reports might be, they continue to appear. With increasing use of minocycline in acne and other conditions, adverse reactions may become increasingly common early recognition is important to prevent further deterioration, to hasten recovery, and to avoid invasive investigations and treatment (2). The authors of this review recommended that safer alternatives be considered in the treatment of acne. 

Tetracycline (chlortetracycline) and oxytetracycline These tetracyclines are incompletely absorbed from the gastrointestinal tract. Plasma concentrations fall with half-lives of 6-12 hours. They are predominantly excreted by the kidney, extrarenal elimination amounting at most to 10-20%. They have a lower affinity for fat and membranes, which means that higher dosages to achieve therapeutic effectiveness. However, higher dosages can contribute to an increased risk of systemic toxic effects and, as absorption from oral administration is incomplete, also to an increased risk of gastrointestinal adverse reactions. 

Committee (SADRAC) in the period 1965-95. There were 23 hver reactions with a snspected cansal relation to oral low-dose tetracychne derivatives. A cansal relation was considered likely in three cases and possible in eight, giving an incidence of ronghly one in 18 million defined daily doses. There were no deaths from these liver reactions, and hver enzyme activities normalized in all cases without any serious chnical consequences. The authors remarked that the frequency of hver reactions resulting from tetracyclines may be somewhat higher, as previous studies in Sweden suggest that only 20-50% of severe adverse reactions are reported to SADRAC (106). 

Adverse reactions to theophylhne are more common in patients who are concurrently taking a tetracycline (SED-9, 4). 

Side effects Adverse reactions Contraindications delay in wound healing None known Anemia, increased LDL cholesterol, muscle pain, fever, nausea, vomiting Do not take with tetracycline. 

Adverse effects might be produced when tetracyclines are administered with other medications. Here are potential adverse reactions ... 

Studies suggest that SOOmg of tetracycline po q 6h could be substituted for doxycycUne. In addition, 400 mg of gatifloxicin or monifloxacin, po daily could be substituted Tf antibiotic susceptibility testing, lack of resources or adverse reactions preclude use of ciprofloxacin... 

Tigecycline is an antiinfective/glycylcycline, which inhibits protein transportation in bacteria by binding to the 30S ribosomal subunit and blocking entry of amino-acyl tKNA molecules into the A site of the ribosome. This prevents incorporation of amino-acid residues into elongating peptide chains. Glycylcycfine class antibiotics are structurally similar to tetracycline class antibiotics and may have similar adverse reactions. 

Risks of using tetracyclines and fluoroquinolones in children must be weighed carefully against the risk for developing a life-threatening disease due to B. anthracis. Both agents can have adverse health reactions in children. If adverse reactions are suspected, theiapy may be changed to amoxicillin or penicillin. 

Only 3 reports of pregnancies were identified in women who took metronidazole and an oral contraceptive (unspecified) in the adverse reactions register of the CSM in the UK for the years 1968 to 1984. A survey of oral contraceptive failure identified one failure due to metronidazole (48 of a total of209 cases were attributed to antibacterials), and a follow-up study identified one fiuther case. Another survey found one contraceptive failure in a woman taking metronidazole, but she was also taking dox-ycycline (see Hormonal contraceptives + Antibacterials Tetracyclines , p.983). It is possible that these cases represent chance associations. 

In contrast, 13 healthy subjects taking lithium carbonate 450 mg twice daily or 900 mg once daily had a small reduction in serum-lithium levels (from 0.51 to 0.47 mmol/L) when they were given tetracycline 500 mg twice daily for 7 days. The incidence of adverse reactions remained largely unchanged, except for a slight increase in CNS and gastrointestinal adverse effects. 

Exceptional adverse reactions of undefined etiology following tetracycline administration do exist. Bean (1971) reported acneiform eruptions occurring in a... 

Fisher AA (1983) Adverse reactions to topical clindamycin, erythromycin and tetracycline. Cutis 32 415, 419, 424, 428... 

Reports of the non-antimicrobial effects of tetracyclines continue to appear, and the clinical uses of non-antimicrobial tetracyclines in dermatology have been highlighted [119 ]. In general, when these drugs are used for non-infectious conditions, adverse reactions seem to be of same types and frequencies as when they are used as antimicrobial agents. However, the adverse effects profiles of the chemically modified tetracyclines have still not been properly elucidated. 

The answer is c. (Hardman, pp 1134-1135.) Hematologic toxicity is by far the most important adverse effect of chloramphenicol The toxicity consists of two types (1) bone marrow depression (common) and (2) aplastic anemia (rare) Chloramphenicol can produce a potentially fatal toxic reaction, the gray baby syndrome, caused by diminished ability of neonates to conjugate chloramphenicol with resultant high serum concentrations. Tetracyclines produce staining of the teeth and phototoxicity... 

Hypersensitivity reactions (drug fever, skin rashes) to tetracyclines are uncommon. Most adverse effects are due to direct toxicity of the drug or to alteration of microbial flora. 

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