Drugs and their categories in pregnancy and breastfeeding-S

Drug	Pregnancy category	Compatibility with breastfeeding
salbutamol	A	compatible
salcatonin	B2	caution, insufficient data
salicylic acid	unlisted	compatible
salmeterol	B3	compatible
saquinavir	B1	insufficient data [Note 1]
selegiline	B2	avoid, insufficient data
selenium sulfide	unlisted	compatible
senna	A	compatible
sennoside B	A	compatible
sertraline	C [Note 2]	probably compatible
sibutramine	C	avoid, insufficient data
sildenafil	B1	not indicated for use in women
silver sulfadiazine	C	compatible
simvastatin	D	avoid, insufficient data
sodium citrate enemas	A	compatible
sodium clodronate	B3	caution, insufficient data
sodium cromoglycate	A	compatible
sodium lauryl sulfoacetate	A	compatible
sodium nitroprusside	C	avoid, insufficient data
sodium phosphate enemas	unlisted	compatible
sodium picosulfate	unlisted	compatible
sodium thiosulfate	unlisted	compatible
sodium valproate	D	compatible
sorbitol	unlisted	compatible
sotalol	C [Note 13]	compatible
spectinomycin	B1	insufficient data
spironolactone	B3 [Note 3]	compatible
stavudine	B3	insufficient data [Note 1]
sterculia	unlisted	compatible
streptokinase	C	caution, insufficient data
streptomycin	D	insufficient data
sucralfate	B1	compatible
sufentanil	unlisted	compatible in occasional doses
sulfamethoxazole+trimethoprim	C	compatible for older, healthy, full-term infants, avoid if possible if the infant is premature or less than 1 month old, monitor infant for haemolysis and jaundice
sulfasalazine	A	caution; may cause diarrhoea in infant
sulfinpyrazone	B2	caution, insufficient data
sulfonamides	C	compatible for older, healthy, full-term infants
sulfur	topical use: unlisted	topical use: compatible
sulindac	C	caution, insufficient data [Note 10]
sumatriptan	B3	caution, insufficient data
suxamethonium	A	caution, insufficient data

Note 1: In Australia, breastfeeding is not recommended for HIV-positive women because of the possibility of HIV transmission. Note 2: Human data are inadequate and the safety of these medications in pregnancy is uncertain. Note 3: Antiandrogens have the potential to feminise the male fetus, avoid in pregnancy. Note 4: Tetracyclines are safe for use during the first 18 weeks of pregnancy (16 weeks postconception) after which they may affect the formation of the baby's teeth and cause discolouration. Note 6: Tricyclic antidepressants have been taken by a large number of pregnant women without any proven increase in the frequency of fetal malformation. In full-term neonates, reversible adverse effects have occasionally been observed, but very rarely cause significant problems. Note 7: Although theophylline has a Category A rating, it does cross the placental barrier. The effect on fetal development is not known. Theophylline clearance is significantly decreased in premature infants. Therefore, if this drug is administered to the mother near the time of delivery, the neonate should be monitored closely for the pharmacological effects of theophylline. Hence the use of theophylline in pregnant women should be balanced against the risk of uncontrolled asthma. Note 8: See also: Cleland LG, James MJ, Proudman SM. Fish oil: what the prescriber needs to know. Arthritis Research and Therapy 2006;8(1):202-11. Note 9: See leflunomide regarding preconception advice and cholestyramine washout. Note 10: If an NSAID is required in a breastfeeding patient, diclofenac or ibuprofen is preferred. Note 11: Absorption of eye drops into the maternal circulation is generally low, although there are occasional reports of systemic effects. Nevertheless, significant transfer into milk is unlikely. Note 12: Large molecular weight proteins/polypeptides are unlikely to transfer into milk. In the absence of specific information, adverse effects in the infant are unlikely. Note 13: Early reports of pregnancy outcomes in women treated with beta blockers in pregnancy, particularly dealing with propranolol, described a relatively high incidence of fetal growth restriction. This appears to be the basis for the C classification of the class of drugs. Since these findings were not from randomised studies, but were clinical descriptions of women who had underlying disorders known to be associated with an increased rate of both intrauterine fetal growth restriction and death, it is not possible to determine whether the described outcomes were due to the therapy or to the disorder for which therapy was prescribed. Subsequent evidence has indicated fetal growth restriction in hypertensive pregnant women treated with atenolol, but better fetal growth in women treated with another beta blocker, oxprenolol, than in women treated with methyldopa. This has been attributed to the intrinsic sympathomimetic activity inherent in this drug. No other fetal or neonatal problems have been attributed to beta-blocker therapy in pregnancy, and they are widely prescribed for the treatment of hypertension in this situation.