The harmful substances that cause Ciguatera, Scombroid, and shellfish poisonings are heat stable, so no amount of cooking will prevent you from becoming poisoned if you eat contaminated fish. Symptoms depend on the specific type of poisoning.
Ciguatera poisoning symptoms can occur 2 to 12 hours after eating the fish. They include:
Shortly after these symptoms develop, you will start to have strange sensations, which may include:
- A feeling that your teeth are loose and about to fall out
- Confusing hot and cold temperatures (for instance, you will feel like an ice cube is burning you, while a match is freezing your skin)
- Headache (probably the most common symptom)
- Low heart rate and low blood pressure (in very severe cases)
- Metallic taste in the mouth
These symptoms may get worse if you drink alcohol with your meal.
Scombroid poisoning symptoms usually occur immediately after eating the fish. They may include:
- Breathing problems, including wheezing and chest tightness (in severe cases)
- Extremely red skin on the face and body
- Hives and itching
- Nausea and vomiting
- Peppery or bitter taste
Below are other well-known types of seafood poisoning, and their symptoms.
Paralytic shellfish poisoning: About 30 minutes after eating contaminated seafood, you may have numbness or tingling in your mouth. This sensation may spread down to your arms and legs. You may become very dizzy, have a headache, and, in some cases, your arms and legs may become temporarily paralyzed. Some people may also have nausea, vomiting, and diarrhea, although these symptoms are much less common.
Neurotoxic shellfish poisoning: The symptoms are very similar to those of Ciguatera poisoning. After eating contaminated clams or mussels, you will most likely experience nausea, vomiting, and diarrhea. These symptoms will be followed soon after by strange sensations that may include numbness or tingling in your mouth, headache, dizziness, and hot and cold temperature reversal.
Amnesic shellfish poisoning: This is a strange and rare form of poisoning that begins with nausea, vomiting, and diarrhea. These symptoms are followed by short-term memory loss, and other less common nervous system symptoms.