Other causes of nausea include side effects from medications, pain, pregnancy and morning sickness, seasickness, viral infection, alcohol toxicity, and disease of the brain, esophagus, stomach, gallbladder, liver, pancreas, and intestine.
so roosevelt was able to win more than two terms because there was not yet a formal term limit on the presidency and the unique conditions when he ran for his third and fourth terms made his arguments for breaking with tradition acceptable to a majority of american voters
How Did FDR Replace His Vice President Twice When It Seems So Politically Challenging Now? Craig Montuori, Executive Director at PolitiHacks and Political Coordinator at Startup Visa The risks to President Roosevelt keeping the same ticket were much higher than the switch in both 1940 and 1944: