Shellfish Poisoning Paralysis Overview
Shellfish poisoning can occur after eating clams, mussels, oysters, scallops, cockles, starfish, and crustaceans that consume dinoflagellates during a red tide. During a red tide, sea waters turn a reddish color because large numbers of red organisms (dinoflagellates) are present. Dinoflagellates kill fish and other organisms by releasing toxins (poisonous substances). Consequently, shellfish take in the concentrated saxitoxin, a poison that causes paralysis.
Red tides are most common in the cold waters of North America, Europe, Africa, Asia, and Japan. A red tide rarely occurs in warmer climates. People are poisoned when they unknowingly eat shellfish contaminated during a red tide with saxitoxins.
Shellfish that is contaminated during a red tide does not have an abnormal taste, smell, or color, and the toxin is not destroyed by heating or cooking. Paralysis due to shellfish poisoning follows a similar progression to that of pufferfish poisoning.
Shellfish Poisoning Paralysis Symptoms
Symptoms of shellfish poisoning begin 30 minutes to 2 hours after eating and include:
Muscle paralysis may occur. The person who has been poisoned may also develop the following conditions:
- Lower-back pain
- Vertigo (dizziness)
- Loss of balance
- Blurred vision
- Temporary blindness
- Elevated heart rate
- Low blood pressure
- Altered temperature perception
Ingesting large amounts of contaminated shellfish can result in coma and respiratory failure.
Shellfish Poisoning Paralysis Treatment
- Do not induce vomiting
- In case of vomiting, turn the person on his or her side to prevent the person from breathing in any stomach contents (vomit).
- The person may become paralyzed.
- Medical liquid charcoal to absorb the toxins may be given as a drink.
- Artificial respiration may keep the person alive until he or she arrives at a hospital's emergency department.
When to Seek Medical Care
Seek medical treatment as soon as possible.