You’ve probably had bad fish before and suffered the digestive consequences. But the ciguatera toxin, an algae-produced substance you can get from eating tropically-sourced fish, delivers a double whammy: first nausea and intestinal trouble, then neurological symptoms that can alter your sense of balance, reality, and touch, as well as cause body aches, depression, anxiety, and painful sex. There are also reports of sufferers feeling a burning or tingling sensation on the bottom of their feet. The scary part? There’s no antidote for the poison. The digestive issues fade within days, but the rest can last anywhere from a week to a year, depending on how your body processes the toxin, though its effects will be strongest if you eat a large portion of the fish and have a lower body weight, says Ruben Olmedo, MD, director of the division of toxicology in the department of emergency medicine at the Mount Sinai Hospital. Your best bet for avoiding it in the first place is to know where your fish comes from. You can check with the Centers for Disease Control for recent outbreaks near you, but in general, fish that hail from warm waters, like the gulf region or Caribbean, are most likely to carry the toxin. The type of fish matters, too: Large species like barracudas, sea bass, red snapper, grouper, amber jack, king fish, sturgeons, parrot fish, and mahi mahi, have the highest levels of toxins in general. “Because it’s in big fish and we eat bigger portions of them, ciguatera is the most common of form of neurological fish poisoning,” Dr. Olmedo says. Like most food poisoning, it will hit your digestive system about 2-6 hours after consumption, but if you start experiencing brain- and sensory-related issues, you should seek medical help for supportive care.
