Brief Answer: Refer below Detailed Answer: Hi, Thanks for consulting HealthcareMagic! What causes foaming at the mouth- Saliva when mixed with mucus in throat combined rapid breathing leads to formation of foam. This can happen typically happens in generalised tonic clonic convulsions. A convulsion is an abnormal electrical activity in the brain which may be because of various reasons like dehydration, head injury, infection in brain, metabolic disturbances such as hypoglycaemia(low glucose levels), hypoxia (low oxygen levels), fever, space-occupying lesions in the brain like abscessesand tumours, certain drugs and few other. Hope I have answered your query. Let me know if you have have any clarifications. If not, you can close the discussion and rate the answer. If you like my answers and wish me to answer in future, bring it to my attention: Dr Vasanth. Url link is as follows: WWW.WWWW.WW Wish you good health!

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