What would happen if someone were to swallow a mouthful of shower gel?

Almost all common body washes are non toxic if small amounts are ingested. A few contain propylene glycol - which is the active ingredient in antifreeze, and even small amounts can cause GI distress, and large amounts (more than a mouthful) can cause renal failure. Most shower gels will just cause local irritation and gagging if swallowed. Call your local poison control with the brand to be sure.

If you are planning to swallow shower gel, bad idea, would not consider it. If you have already swallowed, then you must have first hand experience of its effects. Please contact poison control center for further instructions. Hope it helps.