In general, vaccines are regarded safe since such substance is not suspected to give an up-regulation of the heme biosynthesis as a direct effect. However, some vaccines can lead to a reaction with high fever persisting over days as a side effect. It is possible that this side effect can trigger an acute porphyric attack in the same way as infections are known to. Vigilance is therefore motivated when administrating a vaccine known to cause reactions with fever.

Fever is reported as a very common side effect the meningococcus A, C, Y, W-135 vaccine. A common adverse reaction of the vaccine that can be confused with an acute porphyric attack is nausea. This side effect may potentially be porphyrinogenic if leading to a decrease in carbohydrate intake.

The active substances in the meningococcus A,C,Y,W-135 vaccine are conjugates of protein and oligosaccharides and with regards to its pharmacokinetics it has no conceivable porphyrinogenic effects.

The tetravalent meningococcus A, C, W, Y-135 conjugate vaccine consists of oligosaccharides derived from capsular polysaccharides of Neisseria meningitidis serogroups A, C, W and Y, each conjugated to a Corynebacterium diphtheriae-mutant carrier protein (EMA).

The Meningococcus A,C,Y,W-135 vaccine is indicated for active immunization of children (from 2 years of age), adolescents and adults at risk of exposure to Neisseria meningitidis groups A, C, W135 and Y, to prevent invasive disease. It is administered by a single intramuscular injection.

The meningococcus vaccine is not metabolized by the cytochrome P450 system.