Potential side effects from taking Goody's Headache Powders include stomach upset, nausea, vomiting, difficulty falling asleep and nervous feelings, according to WebMD. Serious but rare side effects requiring emergency medical attention include fainting or severe dizziness, continuing or increased stomach pain, coffee ground-like vomit, irregular heart beat and hearing loss.
Goody's Headache Powders are temporary pain relievers that blend acetaminophen, aspirin and caffeine, notes WebMD. Excessive doses of acetaminophen can lead to serious and potentially deadly liver disease. Acetaminophen works with aspirin to relieve mild to moderate pain, and caffeine intensifies their effects. Goody's powders soothe the pain of head and body aches, fever, arthritis and colds, according to Prestige Brands Holdings.