Appropriate medical treatment must be available & provide close supervision if rare anaphylactic reactions occur following vaccination. Do not administer intravascularly. Individuals w/ thrombocytopenia or bleeding disorders. May induce reduced immune response during immunosuppressive treatment or immunodeficiency condition; wait until the end of treatment before vaccinating. May recommended in individuals whom oral vaccine is contraindicated, & as booster for those previously vaccinated w/ oral vaccine. Syncope may occur; place procedures to prevent injury due to fainting. Contains phenylalanine which may be dangerous for patients w/ phenylketonuria; ethanol 2 mg/dose & Na 23 mg/dose. May be prescribed during pregnancy in high risk situations. Consider potential risk of apnoea & need for resp monitoring for 48-72 hr when administering primary immunisation series to very premature infants (≤28 wk of gestation) & particularly for those w/ history of resp immaturity.