Which of the following instructions should be given to a lactating mother regarding drug usage?

Just before the next dose, the plasma concentration of drug is minimum; so it is relatively safer to feed at that time. Some drugs are secreted significantly in milk. There is no relation between half-life of a drug and its milk secretion ; So, long half life drugs may also come in milk. Not all the drugs are harmful or significantly secreted in milk so feed should not be stopped. Drugs C/I during lactation: Lithium Aspirin Levetiracetam Atenolol Sulfonamide Metronidazole Methotrexate Metals(Cu).