The pain in the tongue when eating betel nut may be caused by betel nut damaging the oral mucosa, and can be treated with oral cidadex iodine tablets under the guidance of a doctor. Betel nut is a toxic substance, long-term consumption of large quantities of betel nut will damage the mucous membrane, resulting in the symptoms of betel nut tongue pain, and in serious cases, it may also cause oral cancer. If you have a sore tongue when eating betel nut, you can take Cetrimide tablets by mouth under the guidance of your doctor for treatment. Eating betel nut will not only cause tongue pain, but also oral cancer in serious cases, and some patients may also suffer from indigestion. If you have a sore tongue from betel nut, you should quit in time and go to a professional hospital to clean your oral hygiene, and when you take medication, you should do it under the guidance of a doctor, and you should not take it on your own to avoid any adverse effects.