What is pellagra? | Symptoms and Treatment | Nutrition


What is pellagra?

Pellagra is a disease caused by low levels of niacin, also known as vitamin B-3. It is characterized by dementia, diarrhoea, and dermatitis, also known as the “Three D’s.” If left untreated, Pellagra can be fatal.

Although it is much less common than in the past, thanks to advances in food production, it is still a problem in most developing countries. It also affects people who do not take niacin correctly.

This is a condition caused by a lack of vitamin B-3, also known as niacin.

It causes many symptoms, but the most common are diarrhoea, dermatitis, and dementia. Without diagnosis and treatment, this disease is fatal.

Symptoms of pellagra

The main symptoms of this disease are dermatitis, dementia, and diarrhoea. Niacin deficiency is most noticeable in parts of the body that have a high rate of cell turnovers, such as the skin or the gastrointestinal tract.

Pellagra-related dermatitis usually causes rashes on the face, lips, legs, or hands. In some people, dermatitis develops around the neck, called a castle collar.

Additional dermatological symptoms:

  • Red and scaly skin
  • Pale areas ranging from red to brown.
  • Thick, crusty, scaly, or cracked skin
  • Itchy skin, burns

In some cases, the neurological signs of pellagra appear early but are very difficult to detect. As the disease progresses, symptoms of dementia include:

  • Indifference
  • Disappointment
  • Confusion, irritability, or mood swings
  • Headache
  • Volatility or anxiety
  • Disorientation or hallucinations

Other characteristics of pellagra:

  • Sores on the lips, tongue, or gums
  • Decreased appetite
  • Eating and drinking problems
  • Nausea and vomiting

 Causes of pellagra

The pellagra diet is low in niacin or tryptophan. It also occurs when the body does not absorb these nutrients.

Pellagra also develops due to:

  • Gastrointestinal diseases
  • Weight loss surgery (bariatric)
  • Anorexia
  • Excessive alcohol consumption
  • Carcinoid syndrome (a group of symptoms associated with bronchial tumours in the intestine, colon, appendix, and lungs)
  • Some medications such as isoniazid, 5-fluorouracil, 6-mercaptopurine

The disease is common in some parts of the world (parts of Africa) where people are more likely to have untreated corn in their diet. Corn is a poor source of tryptophan and the niacin in corn is strongly bound to other components of the grain. Niacin is released from corn when it is soaked in lime water overnight. This method is used to cook tortillas in Central America, where pellagra is rare.

Risk factors

Alcohol can prevent some proteins from turning into niacin, which increases the risk of developing this disease.

However, the alcohol-induced disease is often not recognized because its appearance is similar to that of alcohol withdrawal forgetfulness.

Other risk factors for secondary pellagra:

  • Homeless malnutrition, anorexia, HIV, or end-stage cancer
  • Crohn’s disease
  • Hartnup disease
  • Dialysis
  • Some medicines such as isoniazid for tuberculosis
  • Carcinoid syndrome, a collection of symptoms caused by carcinoid tumours.


Pellagra disease is difficult to diagnose because it causes a wide variety of symptoms. There is also no specific test to diagnose niacin deficiency.

Instead, your doctor will start by checking for gastrointestinal problems, rashes, or changes in your mood. They can also test your urine.

In many cases, a diagnosis of this disease is to see if your symptoms respond to niacin medication.


Pellagra treatment begins with seeking medical attention from your healthcare provider. To find out if you have the disease, your healthcare provider will ask you questions, request a blood sample, and prescribe a diagnostic test. It is very important to strictly follow your treatment plan for pellagra and to take all medications as prescribed.

Pellagra’s treatment approach depends on treating the root cause of the disease. Niacin and tryptophan (if necessary) return to normal levels during treatment. Maintaining supplements can help replenish these substances until the balance is restored.

Your healthcare provider will provide specific recommendations for your specific niacin needs based on your age, gender, and health.

Primary pellagra is treated with dietary changes and with a niacin or nicotinamide supplement. It must also be administered intravenously. Nicotinamide is another form of vitamin B-3. With early treatment, most people make a full recovery and feel better within a few days of starting treatment. The improvement of the skin can take several months. However, if left untreated, primary pellagra usually causes death, four to five years later.

Secondary treatment with the disease generally focuses on treating the underlying cause. However, some cases of secondary pellagra also respond well to taking niacin or nicotinamide by mouth or intravenously.

When recovering from primary or secondary pellagra, it is important to protect any rash with moisture and sunscreen.

Living with pellagra

Pellagra is a serious condition caused by low levels of niacin due to malnutrition or absorption problems. If left untreated, it can cause death. While primary pellagra responds well to niacin replacement, secondary pellagra is difficult to treat, depending on the cause.

Share on facebook
Share on google
Share on twitter
Share on linkedin
Share on pinterest

Leave a Reply

Your email address will not be published. Required fields are marked *