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 C 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 C vaccine are conjugates of protein and oligosaccharides and with regards to its pharmacokinetics it has no conceivable porphyrinogenic effects.

The meningococcus C, purified polysaccharides antigen conjugated vaccine is composed of a meningococcal group C polysaccharide conjugated to a tetanus toxoid protein, a chemically detoxified form of tetanus toxin, adsorbed onto aluminum hydroxide (Pfizer, product monograph)

The meningococcus C vaccine is indicated for active immunization in children from 2 months of age, adolescents and adults, for the prevention of invasive disease caused by Neisseria meningitidis serogroup C. It is administered by intramuscular injection. In children and adults one dose is sufficient while infants may need two or three doses.

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