Background information

This information applies only to treatment of patients with an acute porphyria (AIP, HCP, VP).

  Evidence on safety of drugs is drawn from three main sources:
Clinical reports
Experimental systems ( e.g. chick embryo hepatocyte culture)
Drug metabolism data
  Combinations of drugs plus other factors (stress, infection, malnutrition) may increase the risk of an acute attack.
  No drug should be withheld if it is judged essential for optimum treatment of a life-threatening condition (e.g. chemotherapy for cancer).
  Response to drugs in patients with an acute porphyria is extremely variable and individuals may be encountered who have used an unsafe drug without adverse effect.