Please be reassured that your cough virus won't pass through breast milk; instead, your milk provides protective antibodies to your baby. To protect your little one, wash your hands frequently and consider wearing a mask while nursing. For relief, try warm fluids, honey (safe for you, but never give honey directly to babies under one year), or saline nasal sprays. If you need medication, generic dextromethorphan or guaifenesin are generally safe, but avoid decongestants like pseudoephedrine as they can decrease your milk supply. Please consult your doctor or lactation consultant before starting any medication to ensure it is the best choice for you both.