It is common for medications used to treat neck pain to cause side effects like heartburn. To alleviate this issue, you can try limiting your use of anti-inflammatory drugs to when absolutely necessary. If the pain is severe, you can also consider taking acetaminophen every 6-8 hours. It's important to take anti-inflammatories with food to reduce the risk of heartburn. Additionally, over-the-counter medications like Tums or Zantac can provide temporary relief. Consult with your local pharmacist to find the right product for you.