You got food poisoning. The restaurant should know about it.

You ate somewhere, spent the night regretting it, and the restaurant should hear about it properly. This writes a formal complaint: what you ate, what happened, that you've told environmental health, and exactly what you want back, so it lands as a serious report rather than an angry review.

Write a formal complaint to [restaurant name] about a meal I had on [date]. Within [timeframe] of eating [dish], I experienced [symptoms]. I have also reported this to my local environmental health team. Request a written response, ask what investigation they will carry out, and state that I expect acknowledgement within 5 working days.