18. Tampa, Florida

Tampa is ranked on the list for having worse-than-average overall pollen levels, receiving a 77.02-point ranking, the study reported.
Grass pollen is a top component here and was reported to affect allergies year-round but peaks in April through mid-October. Tampa has a worse-than-average rate for the amount of medicine used but has an average ranking for the number of people who ultimately need to seek specialist care.