A nutritional supplement, not a substitute for prescribed treatment. NAC has a distinctive sulphur smell, which is normal. Tell your doctor before use if you have asthma, a bleeding disorder, stomach ulcers, or take nitrate heart medicines or blood thinners. Stop and seek advice for any rash, wheeze or stomach upset. Not recommended in pregnancy or breastfeeding without medical advice. Store in a cool, dry place. This product information is for general guidance only and does not replace professional medical advice. Always consult a qualified healthcare provider before starting any new medication or supplement. Keep out of reach of children.