8 months post-op. When I gag my stomach tightens like a Charlie horse. Can there be something wrong internally?

Thank you for sharing your question and I am sorry to hear of the muscle spasms.  Some patients can have activation of their stomach muscles like a cramp that can develop in the legs.  Typically this improves over time and fully resolves once your results and tissues fully heal.  If this has not, see your surgeon for an in-person discussion and evaluation.  

Thank you for your question. This sensation your having is unusual. This sounds like a muscle spasm but why this occurs while brushing your teeth is unexplainable. At 8 months, you should be well healed. from your tummy tuck. I would see your family doctor to work up this problem if it continues. Medical issues such as a hiatal hernia or reflux esophagitis could be reasons but further testing will be needed.