English Medical Idioms / Maxims / Sayings scientific

I failed to find a specific explanation for this expression in any dictionary available to me. Is there a stable meaning for "if warranted"?

Please explain the meaning of these two words in the following sample contexts (especially the second one):

(1)
Many guidelines now suggest deferring the start of antibiotics for one to three days[6] avoiding the need for antibiotics for two out of three children[7] without adverse effect on longterm outcomes for those whose treatment is deferred.[8] First line antibiotic treatment, if warranted, is amoxicillin.

(2)
Pharmacokinetics parameters, clearance, and possibly volume if warranted, of [substance] and its metabolites will be determined using specific statistical modeling.

(3)
Our qualified asbestos consultants also render an opinion as to the appropriate course of action and provide cost estimates for remediation, if warranted.