dosage vs recall dose

dosage and recall dose both are nouns.

Word	Noun	Adjective	Verb	Adverb
dosage	Yes	No	No	No
recall dose	Yes	No	No	No

As nouns, recall dose is a hyponym of dosage; that is, recall dose is a word with a more specific, narrower meaning than dosage:

dosage: a measured portion of medicine taken at any one time
recall dose: an additional dose that makes sure the first dose was effective

dosage (noun)	recall dose (noun)
a measured portion of medicine taken at any one time	an additional dose that makes sure the first dose was effective
the quantity of an active agent (substance or radiation) taken in or absorbed at any one time