| Drug Classification | Advice for prescription |
|---|---|
| Not porphyrinogenic (NP) | Used as a first-hand choice. No precautions needed. |
| Probably not porphyrinogenic (PNP) | Used as a first-hand choice. No precautions needed. |
| Possibly porphyrinogenic (PSP) | Only used when no safer alternative is available. Precautions motivated in vulnerable patients. |
| Probably porphyrinogenic (PRP) | Rescripted only on strong or urgent indications. Precaution motivated in all patients. |
| Porphyrinogenic (P) | Prescribed only on urgent indications. Precaution taken in all patients. |
| Not yet classified (NC) | Not yet safely classified and should therefore not be used. Prescribed only on strong indications when no safer alternative is available. Seek advice from a porphyria specialist. |