Common adverse reactions of the oral typhoid vaccine that can be confused with an acute porphyric attack are abdominal pain, nausea, diarrhoea, vomiting. These side effects may potentially be porphyrinogenic if leading to a decrease in carbohydrate intake. Also fever and influenza-like illness are common side effects of the vaccine and it is possible that this can trigger an acute porphyric attack in the same way as infections are known to.

Based on the pharmacokinetics of the typhoid, oral, live attenuated vaccine, there are no conceivable porphyrinogenic effects.

Live attenuated salmonella enterica serovar Typhi.

For active immunization against typhoid fever in children aged 6 years and over, adults and elderly. The vaccine is administered orally, in form of three capsules taken over five days.