Courses
Courses for Kids
Free study material
Offline Centres
More
Store Icon
Store

Pellagra and Niacin Deficiency Disease Explained

share icon
share icon
banner

What Is Pellagra Causes Symptoms Diagnosis and Treatment

One of the rare diseases that are fatally affecting the lives of people would have to be Pellagra. While there is not much information about the disease, we have tried our best to provide all the details that people need to know about it. Since it is a very rare disease, there are some important pieces of information such as the symptoms and the treatment options that people need to know about. This is why we have compiled all the details regarding the Pellagra disease so that people can know to get a better understanding of the disease.

[Image will be Uploaded Soon]

What is Pellagra?

Often caused due to the lower levels of niacin which is also known as Vitamin B-3, Pellagra is a disease that affects many parts of the body. The main marks of Pellagra are diarrhoea, dementia, and acute dermatitis. These are the three “D’s” that are associated with the disease. If the disease remains untreated for a very long time and the patient doesn’t get any medical attention, it can be quite fatal for them. The disease might not be as common as the other ones but there are still more cases in developing countries. This is due to the major advancements in the food industry. Apart from that, Pellagra can also be seen in people who don’t absorb Niacin in their bodies. We hope that this clears out the question of what is pellagra.

Know All About the Symptoms of Pellagra

Some of the most common symptoms that are seen in people suffering from Pellagra would be diarrhoea, dementia, and dermatitis. This might be attributed to the fact that there is a niacin deficiency in the body of the person. This causes cell turnover and hence causes the gastrointestinal tract and the skin to have problems. When it comes to pellagra definition, it can be said that having lower levels of Vitamin B-3 can cause this disease.

When there is a case of dermatitis that is in relation to pellagra, there are often several rashes found in the lips, face, hands, and feet of the patient. Apart from that, dermatitis can also occur in the neck of the person and that case is known as Casal Necklace.

[Image will be Uploaded Soon]

Some Symptoms might Include:

  • Flaky and red skin

  • Discolouration in several areas of the skin

  • Cracked, scaly, crusty, or thick skin

  • Itching and burning sensations on the skin

Apart from That, There is an Onset of Dementia in the Patients as Well. the Symptoms of This Problem might Include:

  • Depression

  • Apathy

  • Headaches

  • Mood Swings, Irritability, and Other Problems

  • Disorientation and Delusions

  • Restlessness or Anxiety

Some Other Symptoms might Include:

  • Sores on the gums and lips

  • Vomiting and nausea

  • Trouble in drinking and eating

  • Decreased appetite

What is Pellagra Caused by?

Before learning pellagra is caused by it, it is important to know the types of the disease. Well, there are two different types of the disease and these are known as primary pellagra and secondary pellagra. In the case of primary pellagra, there is a deficiency of tryptophan or niacin in the body. Tryptophan is often converted into niacin and hence not getting enough of it might lead to the deficiency of the vitamin in the body of a patient.


In the case of secondary pellagra, the body isn’t really able to properly absorb niacin and that can cause problems. Some of the major causes of the pellagra disease are:

  • Eating disorders

  • Alcohol consumption

  • Liver cirrhosis

  • Different gastrointestinal diseases that include ulcerative colitis and Crohn’s disease

  • Hartnup disease

  • Carcinoid tumours

Information About Pellagra Disease Diagnosis

It can be a difficult task to diagnose this particular disease due to the wide range of symptoms that it has. Not to mention that there isn’t a proper test that can be used for the diagnosis of a niacin deficiency in the body. However, the doctor might be able to diagnose the disease by looking through any changes in your mental state and skin issues along with gastrointestinal problems as well. The doctor might also want to test your urine in order to make sure. There are certain cases where the diagnosis of pellagra involves checking if the symptoms respond to different supplements containing niacin.

Information About the Treatment of Pellagra

There are different methods for treating the different types of pellagra disease. For example, in the case of primary pellagra, the treatment will involve several changes in the diet along with a nicotinamide or niacin supplement. The dosage has to be intravenous in nature. Nicotinamide can be considered a great supplement filled with Vitamin B-3 and hence is used in the treatment process. If the primary pellagra case is treated early, then the recovery doesn’t take much longer.

In fact, you might start to feel a lot better just after having the treatment for a few days. The improvement of skin might take some time. However, if proper treatment is not provided, then primary pellagra can prove to be fatal in about 4-5 years. Secondary pellagra on the other hand uses the treatment to diminish the underlying problems. However, certain supplements of niacin also prove to be helpful in the case of secondary pellagra treatment.

Want to read offline? download full PDF here
Download full PDF
Is this page helpful?
like-imagedislike-image

FAQs on Pellagra and Niacin Deficiency Disease Explained

1. What is pellagra?

Pellagra is a nutritional deficiency disease caused by a lack of niacin (vitamin B3) or its precursor tryptophan in the diet. It primarily affects the skin, digestive system, and nervous system. Pellagra is classically characterized by the “3 Ds”:

  • Dermatitis – skin inflammation and rash
  • Diarrhea – gastrointestinal disturbances
  • Dementia – neurological and cognitive impairment
If untreated, it may progress to a fourth D: Death.

2. What causes pellagra?

Pellagra is caused by a deficiency of niacin (vitamin B3) or inadequate conversion of tryptophan into niacin in the body. Common causes include:

  • Poor diet lacking in protein or niacin-rich foods
  • Heavy dependence on untreated maize (corn)
  • Chronic alcoholism
  • Malabsorption disorders (e.g., Crohn’s disease)
  • Conditions like Hartnup disease that impair tryptophan absorption
These factors reduce the body’s ability to synthesize essential coenzymes.

3. What are the symptoms of pellagra?

The main symptoms of pellagra are dermatitis, diarrhea, and dementia due to niacin deficiency. Key clinical features include:

  • Dermatitis: Symmetrical, sun-exposed rash with thickened, pigmented skin
  • Diarrhea: Inflammation of the gastrointestinal tract
  • Dementia: Confusion, memory loss, depression
Other symptoms may include glossitis (inflamed tongue), fatigue, and irritability.

4. Why does niacin deficiency cause pellagra?

Niacin deficiency causes pellagra because niacin is essential for forming the coenzymes NAD (nicotinamide adenine dinucleotide) and NADP, which are vital for cellular metabolism. These coenzymes are required for:

  • Cellular respiration and ATP production
  • DNA repair and synthesis
  • Fatty acid and cholesterol metabolism
Without sufficient NAD and NADP, high-energy tissues like skin, brain, and gut are most affected.

5. What is the “3 Ds” of pellagra?

The “3 Ds” of pellagra are dermatitis, diarrhea, and dementia. These represent the major systems affected by niacin deficiency:

  • Dermatitis: Photosensitive skin lesions
  • Diarrhea: Gastrointestinal inflammation
  • Dementia: Neurological and cognitive impairment
If untreated, a fourth D—Death—may occur.

6. How is pellagra diagnosed?

Pellagra is diagnosed mainly based on clinical symptoms and dietary history. Doctors look for:

  • Presence of the 3 Ds
  • History of poor nutrition or alcoholism
  • Rapid improvement after niacin supplementation
Laboratory tests may show low levels of niacin metabolites, but diagnosis is often clinical.

7. How is pellagra treated?

Pellagra is treated with supplementation of niacin (nicotinamide) and correction of dietary deficiencies. Treatment includes:

  • Oral or intravenous niacin
  • High-protein, balanced diet
  • Treatment of underlying conditions (e.g., alcoholism, malabsorption)
Symptoms often improve rapidly once proper vitamin B3 levels are restored.

8. What foods prevent pellagra?

Pellagra can be prevented by consuming foods rich in niacin and tryptophan. Important sources include:

  • Meat (chicken, beef, liver)
  • Fish
  • Eggs and dairy products
  • Legumes and peanuts
  • Whole grains and fortified cereals
A balanced protein-rich diet supports adequate niacin synthesis.

9. What is the difference between primary and secondary pellagra?

Primary pellagra results from inadequate dietary intake of niacin, while secondary pellagra occurs when the body cannot absorb or utilize niacin properly. The differences include:

  • Primary pellagra: Poor nutrition or maize-based diet
  • Secondary pellagra: Alcoholism, malabsorption, liver disease, or metabolic disorders
Both types lead to similar clinical symptoms.

10. Why is pellagra common in maize-based diets?

Pellagra is common in maize-based diets because niacin in untreated maize is biologically unavailable and low in tryptophan. Specifically:

  • Niacin is bound in a form called niacytin, which is poorly absorbed
  • Maize is deficient in tryptophan, the precursor of niacin
Traditional alkali treatment (nixtamalization) can release bound niacin and reduce the risk of pellagra.


Competitive Exams after 12th Science
tp-imag
bottom-arrow
tp-imag
bottom-arrow
tp-imag
bottom-arrow
tp-imag
bottom-arrow
tp-imag
bottom-arrow
tp-imag
bottom-arrow