Pregnancy aminoglycosides

Czeizel AE, Rockenbauer M, Olsen J, Sorensen HT A teratological study of aminoglycoside antibiotic treatment during pregnancy. Scand J Infect Dis 2000 32 309-313. 

Accelerated drug elimination is also a possible reason for failure and may occur in patients with cystic fibrosis or during pregnancy, when more rapid clearance or larger volumes of distribution may result in low serum concentrations, particularly for aminoglycosides. 

Nephrotoxicity/Ototoxicity Because of reported cases of deafness and potential nephrotoxic effects, closely observe patients. Refer to the Warning Box in the Aminoglycosides, Parenteral monograph concerning aminoglycoside toxicity. Pregnancy. 

Pregnancy All antibiotics cross the placenta. Adverse effects to the fetus are rare, except for tooth dysplasia and inhibition of bone growth encountered with the tetracyclines. However, some anthelmintics are embryotoxic and teratogenic (p. 359). Aminoglycosides should be avoided in pregnancy because of their ototoxic effect in the fetus. 

Streptomycin use during pregnancy may lead to hearing loss in the newborn, including complete deafness. Streptomycin and the other aminoglycosides must be reserved for critical situations where alternatives do not exist. Although the pol5q>eptide capreomycin has not been studied, it probably carries the same risks. 

Electrolyte imbalance, and diseases that lead to electrolyte imbalance, such as adrenal cortical insufficiency, alter neuromuscular blockade. Depending on the nature of the imbalance, either enhancement or inhibition may be expected. Magnesium sulfate, used in the management of toxemia of pregnancy, enhances the skeletal-muscle-relaxing effects of pancuronium. Antibiotics such as aminoglycosides, tetracyclines, clindamycin, lincomycin, colistin, and sodium colistimethate augment the pancuronium-induced neuromuscular blockade. Anesthetics such as halothane, enflurane, and isoflurane enhance the action of pancuronium, whereas azathioprine will cause a reversal of neuromuscular blockade. 

Papich and Riviere report marked variability in aminoglycoside pharmacokinetics (distribution, clearance, and half-life) with altered physiologic or pathologic states, including pregnancy, obesity, dehydration, immaturity, sepsis, endotoxemia, and renal disease. The latter influence is predictable from the fact that body clearance is dependent almost entirely on renal excretion. Martin-Jimenez and Riviere concluded that aminoglycoside pharmacokinetics can be predicted across species by population pharmacokinetic modeling. ... 

---