breathalyse vs breathalyze

breathalyse and breathalyze both are verbs.

Word	Noun	Adjective	Verb	Adverb
breathalyse	No	No	Yes	No
breathalyze	No	No	Yes	No

As verbs, breathalyse and breathalyze are synonyms defined as:

breathalyse and breathalyze: test someone's alcohol level in his blood by means of a breathalyzer

breathalyse (verb)	breathalyze (verb)
test someone's alcohol level in his blood by means of a breathalyzer	test someone's alcohol level in his blood by means of a breathalyzer