flare up vs break open

flare up and break open both are verbs.

Word	Noun	Adjective	Verb	Adverb
flare up	No	No	Yes	No
break open	No	No	Yes	No

As verbs, flare up and break open are synonyms defined as:

Other synonyms of flare up include burst out, erupt, flare, irrupt.

flare up (verb)	break open (verb)
erupt or intensify suddenly	erupt or intensify suddenly
ignite quickly and suddenly, especially after having died down	come open suddenly and violently, as if from internal pressure
	open with force