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
Only Franklin D. Roosevelt served more than 2 terms. He served 3 and was elected to a fourth term, but died in the first year. Washington set a precedent when he chose not to run for re-election in 1796 after serving only 2 terms. Future presidents followed his precedent until 1940 when Roosevelt ran for a third term.