Acute porphyrias often present with severe and potentially life-threatening manifestations that require prompt diagnosis and treatment. Most notable in terms of emergent presentations are the neurovisceral attacks that occur in the four acute porphyrias (acute intermittent porphyria (AIP), hereditary coproporphyria (HCP), variegate porphyria (VP), ALA dehydratase porphyria (ADP)) and the rare “hepatic crises” in erythropoietic protoporphyria (EPP). Porphyria cutanea tarda (PCT) causes chronic blistering skin lesions but is not considered an emergent condition. Sensitive screening tests can rapidly diagnose these disorders and enable prompt initiation of specific and effective treatment. Specific therapies for the acute porphyrias are hemin and glucose loading. Protoporphyria hepatopathy may respond to medical therapy that includes plasmapheresis and hemin but often requires liver transplantation.