Which of the following drug is safe during pregnancy?
AMPICILLIN: It is active against all organisms sensitive to PnG; in addition, many gram-negative bacilli, e.g. H. influenzae, E. coli, Proteus, Salmonella and Shigella are inhibited. However, due to widespread use, many of these have developed resistance; usefulness of this antibiotic has decreased considerably. Pharmacokinetics: Ampicillin is not degraded by gastric acid; oral absorption is incomplete but adequate. Food interferes with absorption. It is paly excreted in bile and reabsorbed-enterchepatic circulation occurs. However, primary channel of excretion is kidney, but tubular secretion is slower than for PnG; plasma halflife is 1 hr. COTRIMOXAZOLE: The fixed dose combination of trimethoprim and sulfamethoxazole is called cotrimoxazole. T rimethoprim is a diaminopyrimidine related to the antimalarial drug pyrimethamine which selectively inhibits bacterial dihydrofolate reductase (DHFRase).Trimethoprim adequately crosses blood-brain barrier and placenta, while sulfamethoxazole has a poorer entry. Moreover, trimethoprim is more rapidly absorbed than sulfamethoxazole--concentration ratios may vary with time. AMINOGLYCOSIDE: PRECAUTIONS AND I NTERACTIONS 1. Avoid aminoglycosides during pregnancy: risk of foetal ototoxicity. 2. Avoid concurrent use of other ototoxic drugs, e.g. high ceiling diuretics, minocycline. 3. Avoid concurrent use of other nephrotoxic drugs, e.g. amphotericin B, vancomycin, cyclosporine and cisplatin. 4. Cautious use in patients past middle age and in those with kidney damage. 5. Cautious use of muscle relaxants in patients receiving an aminoglycoside. 6. Do not mix amino glycoside with any drug in the same syringe/infusion bottle. CHLORAMPHENICOL :is rapidly and completehabsorbed after oral ingestion. It is 50-60% bound to plasma proteins and very widely distributed volume of distribution 1 L/kg. It freely penetrate;o serous cavities and blood-brain barrier: CSF concentration is nearly equal to that of unbound drug in plasma. It crosses placenta and is secreted in bile and milk. ESSENTIALS OF MEDICAL PHARMACOLOGY K.D.TRIPATHI SIXTH EDITION PAGE NO:685,700,716,722
Aminoglycoside
Ampiclillin
Chloramphenicol
Cotrimoxazole
Chemotherapy