The mnemonic
The three Ds
What each word stands for
- DermatitisSun-exposed skin rash (Casal necklace)
- DiarrhoeaGastrointestinal involvement
- DementiaNeuropsychiatric features
Why it matters clinically
Identifies niacin deficiency, seen with maize-based diets and alcoholism.
Where it stops being reliable
Late-stage features; a fourth D, death, follows if untreated, and early disease may be subtle.
Teaching aid, still awaiting independent review. Confirm facts in a standard source.