Food poisoning from shellfish symptoms

Raw or undercooked shellfish can carry germs or toxins. Food poisoning from shellfish commonly presents with nausea, vomiting, watery diarrhoea, abdominal cramps, and sometimes fever. Symptoms may start after a meal, but timing varies with the cause. Tingling, numbness, weakness, trouble walking, or breathing difficulty are not typical stomach upset and may indicate a toxin-related emergency or an allergic reaction.

Tell a clinician what shellfish you ate, whether it was raw, and whether anyone else became ill. This information can guide the assessment even when the food is no longer available.

If symptoms are mild and you can drink, take frequent sips of water or [Oral Rehydration Therapy](/treatments/acute-and-urgent-care/oral-rehydration-therapy/). Rest and eat bland foods as your appetite returns. Do not eat more of the suspected shellfish, and keep the packaging or venue details if available.

Do not wait for stomach symptoms to settle if you develop swelling of the lips or tongue, wheezing, difficulty breathing, faintness, or widespread hives. Severe fluid loss may be treated with [IV Fluid Therapy](/treatments/acute-and-urgent-care/iv-fluid-therapy/).

Seek emergency care for breathing difficulty, facial or throat swelling, collapse, confusion, new numbness, severe weakness, or trouble walking. Seek urgent medical advice for blood in stool or vomit, severe pain, inability to keep fluids down, or very little urine. Get prompt advice for a child, older adult, pregnant person, or person with a serious medical condition who becomes unwell.

Ask whether your symptoms fit [Food Poisoning](/conditions/food-poisoning/), whether an allergy or toxin is possible, what warning signs to monitor, and which fluids or medicines are appropriate.