intumesce vs swell up

intumesce and swell up both are verbs.

Word	Noun	Adjective	Verb	Adverb
intumesce	No	No	Yes	No
swell up	No	No	Yes	No

As verbs, intumesce and swell up are synonyms defined as:

Other synonyms of intumesce include swell, tumefy, tumesce.

intumesce (verb)	swell up (verb)
expand abnormally	expand abnormally
move upwards in bubbles, as from the effect of heating; also used metaphorically