Megaloblastic Anemia Symptoms

Megaloblastic anemia is a type of anemia that is usually caused by deficiency of cobalamin (vitamin B12) and folate, the two vitamins that have role on Red Blood Cells development.

As there is deficiency of the above mentioned vitamins, so there is failure of RBC development that results in large red blood cells (RBC) with immature cells and early destruction of red blood cells. It results less number of RBC in blood.

Megaloblastic Anemia Symptoms

Patient with megaloblastic anemia may have no symptoms. Based upon the severity of anemia, the symptoms appear. Initially, the symptoms are mild. But as the disease progresses to its severe form, many more symptoms appear with time.

The main clinical symptoms of megaloblastic anemia are same as anemia. The symptoms can be

  1. Anorexia (usually marked)- A disorder where there is loss of appetite for food. Patients with this disorder refuses to take food to lose weight.
  2. Weight loss
  3. Diarrhea
  4. Constipation
  5. Glossitis- It is a condition where there is inflammation of the tongue.
  6. Angular cheilosis- A condition where there is fissures at the corners of the mouth. It is usually due to vitamin B12 deficiency.
  7. Mild fever in more severely anemic patients
  8. Jaundice (unconjugated)
  9. Reversible melanin skin hyperpigmentation- Here the skin hyperpigmentation can come back to normal if therapy is given.
  10. Bruising (due to thrombocytopenia)
  11. Infections particularly in respiratory and urinary tract (due to anemia and low leukocyte count)
  12. Fatigue and weakness

Megaloblastic Anemia Neurologic or Nerve Symptoms

In megaloblastic anemia, there is vitamin B12 deficiency. Vitamin B12 is an important vitamin that helps in the myelination of the central nervous system (CNS). So, deficiency of vitamin B12 can cause

  1. Bilateral peripheral neuropathy
  2. Degeneration (demyelination) of the cervical and thoracic tracts of the spinal cord and sometimes the cranial nerves and white matter of the brain.
  3. Optic atrophy
  4. Dementia
  5. Depression
  6. Psychotic Symptoms
  7. Cognitive impairment
  8. Anosmia (loss of sense of smell)
  9. Loss of taste
  10. Visual impairment
  11. Paresthesia- It is an abnormal tingling or pricking sensation, usually in the hands, arm, leg, feet. It can also be felt in the other parts of the body.
  12. Muscle weakness
  13. Difficulty in walking
  14. Postural hypotension- It is a condition where low blood pressure occurs when one stands up from sitting or lying down position.
  15. Impotence
  16. Incontinence

The Psychiatric Symptoms are

  • “Megaloblastic madness”
  • Mania
  • Paranoia- It is a mental disorder where there is feeling of extreme distrust, suspicion and a feeling of being targeted by others to harm the person. It is an unreasonable feeling which is characterized by delusions.
  • Irritability
  • Delusions
  • Emotional liability
  • Depression

Long term vitamin B12 (cobalamin) deficiency in infancy causes

1. Poor brain development

2. Impaired intellectual development

3. Feeding difficulty


5. Movement disorders

6. Convulsions

7. Coma

Megaloblastic Anemia General Tissue Effects

General tissue effects in megaloblastic anemia are due to cobalamin and folate deficiency. The affected epithelial or superficial surfaces are in the

  • Mouth
  • Stomach
  • Small intestine
  • Respiratory tract
  • Urinary tract
  • Female genital tract

As a result, one can experience fissures at the corners of the mouth, rough surface area, etc.

Megaloblastic Anemia Pregnancy Complications

Pregnancy must be safe and blissful. We guided in a different article how to handle the pregnancy in a safe way. Sometimes vitamin deficiency occurs unknowingly. When the deficiency occurs during pregnancy, it may cause unwanted effects.

Due to the deficiency of folate and cobalamin the following effects are seen which can be described as complications of pregnancy.

  1. Gonads are affected- Gonads can be affected both in men and women.
  2. Infertility- Infertility can occur both in men and women.
  3. Premature birth
  4. Recurrent fetal loss or abortion
  5. Neural tube defects of the newborn
  6. Cleft palate of the newborn
  7. Harelip of the newborn

Megaloblastic Anemia Cardiovascular (heart and blood vessel) Symptoms

The cardiovascular or heart or blood vessel related symptoms include

  1. Ischemic heart disease
  2. Cerebrovascular disease
  3. Pulmonary embolus
  4. Peripheral vascular disease
  5. Coronary heart disease
  6. Deep vein thrombosis

All the above mentioned symptoms can occur in other diseases also. But patients with megaloblastic anemia can show these symptoms in a wide range.

A person may not have all the symptoms, especially when the anemia is in its mild stage. But when the deficiency of vitamins become more, the severity of the anemia increases. As a result, many of the above mentioned symptoms start to appear.

If a person shows the above mentioned symptoms, the blood tests should be done to confirm the diagnosis. Based on the presence of the symptoms, one can not confirm that the condition is megaloblastic anemia. There are many other conditions where the above mentioned symptoms can occur. Blood test report must be correlated with the symptoms.

If a person has many of the symptoms as mentioned above, there is a high chance that the person is suffering from megaloblastic anemia.

Megaloblastic anemia is a treatable condition. So one should not ignore the symptoms. You should always mention all the symptoms (you are experiencing) to your doctor.

More earlier this condition is diagnosed, there is more earlier chance of recovery. Stay healthy and happy.


  1. Psychiatry, 2 Volume Set Book By Wiley
  2. Year Book of Psychiatry and Applied Mental Health 2012
  3. Textbook of Psychiatry E-Book, Elsevier
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