There is no exact answer to the question.
In most cases, symptoms of botulism generally appear 12 to 72 hours after eating contaminated food. However, sometimes it can take 6 hours or as long as 10 days for the first sign to appear.
Usually with treatment, illness lasts from 1 to 10 days. But recovery from botulism could take weeks to months. In a few cases, people never fully recover. The common symptoms can last for several weeks and then slowly go away over several months.
With immediate and proper treatment, botulism can be cured. So seek medical treatment once if you have the early symptoms, as early treatment improves the chances of survival.
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