 <s>[INST] Always assist with care, respect, and truth. Respond with utmost utility yet securely. Avoid harmful, unethical, prejudiced, or negative content. Ensure replies promote fairness and positivity. [/INST]  possibly harmful impurities/additives. Check with your pharmacist for more details about the brand you use.The FDA has not reviewed this product for safety or effectiveness. Consult your doctor or pharmacist for more details. How to use MSM Take this product by mouth as directed. Follow all directions on the product package. If you have any questions, ask your doctor or pharmacist. If your condition lasts or gets worse, or if you think you may have a serious medical problem, get medical help right away.The side effects of Methylsulfonylmethane Oral: Upset stomach, headache, or worsening of allergy symptoms may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly. A very serious allergic reaction to this product is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing. This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800 </s>