Panhematin

Panhematin is a brand-name intravenous preparation of hemin used to treat acute porphyrias. The active ingredient is hemin, a form of heme, administered by intravenous infusion in hospital settings. It is approved for the treatment of acute attacks in porphyrias, including acute intermittent porphyria, variegate porphyria, and hereditary coproporphyria, to relieve neurovisceral symptoms and prevent progression.

Mechanism of action: Panhematin provides exogenous heme, which exerts negative feedback on hepatic ALA synthase-1, the rate-limiting enzyme in heme synthesis. This reduces the production of porphyrin precursors such as ALA and porphobilinogen, helping to alleviate symptoms and normalize metabolic processes during an attack.

Administration and dosing: therapy is typically given as an IV infusion at about 4 mg/kg per day for four consecutive days. Dosing may be adjusted by the treating clinician based on clinical response and tolerability. In some cases, repeated or extended courses may be considered.

Adverse effects: common adverse effects include fever, infusion-site reactions such as phlebitis or pain, headache, and nausea. Hypersensitivity reactions and, rarely, anaphylaxis have been reported. Repeated courses may necessitate monitoring of iron status to prevent iron overload.

Contraindications and precautions: Panhematin should be used with caution in patients with iron overload disorders. Careful monitoring is advised in individuals with hepatic impairment and during intravenous administration to manage potential infusion-related reactions.

Storage: store as directed, typically with refrigeration and protection from light.