These are some of the links we found to have the best information about porphyria:

American Porphyria Foundation
A good source of information. This site has online newsletters, discusses available treatment options, and hosts group telephone conference calls with specialists (for members). Worth a visit.

Canadian Porphyria Foundation
A good resource on porphyria. Unfortunately, lack of funding in 2009 has forced the group to curtail many of its activities. You can still find online newsletters and other useful information on its website.

Porphyria Association Inc. (Australia)
A voluntary non-profit organisation, they have basic information about porphyria and website links to safe/unsafe drug lists for porphyria patients.  See this link for the Drug Database for Acute Porphyria.

Medline Plus on Porphyria
This site is sponsored by the US National Library of Medicine and the National Institutes of Health. It contains reliable information about porphyria.

"Porphyria" at the National Digestive Diseases Information Clearinghouse (NDDIC)
A USA site sponsored by the National Institutes of Health. It contains reliable information about porphyria.

The National Research Centre for Environmental Toxicology, University of Queensland
This site contains an information site for porphyria patients.

New Zealand medical perspectives

Clinical indications for the investigation of porphyria: case examples and evolving laboratory approaches to its diagnosis in New Zealand.  By C. Sies, C. Florkowski, P. George, and H. Potter.  New Zealand Medical Journal, 16 Sept 2005, vol. 118, no. 1222  (This article is available for free online and provides explanation of the various types of porphyria.)