Introduction

Normocytic anemia is a type of anemia where the red blood cells are uniform in size however, there is a lower-than-normal amount of red blood cells within the blood. In normocytic anaemias, the red blood cells have a mean corpuscular volume of 80-100 fl,³ this happens to be the healthy size of red blood cells for individuals without anaemia.⁴ This is different from other types of anemias, such as macrocytic or microcytic anemia, where the red blood cells are too big or too small.¹

Importance of recognising symptoms

Recognising the symptoms of normocytic anemia is important, as it is often a sign of an underlying health condition. Early diagnosis of such conditions can lead to better long-term outcomes. Additionally, if normocytic anemia is linked to another medical issue, further testing may be necessary to manage the condition properly.²

Causes of normocytic anaemia: a brief overview

Normocytic anemia can have several causes. It may result from significant blood loss, such as heavy menstrual bleeding or bleeding from long-term conditions, which are often related to the digestive system. Certain inherited blood disorders, like sickle cell disease,¹⁹ thalassemia, and G6PD deficiency, can also lead to normocytic anemia.⁶ Other possible causes include an overactive spleen, liver disease, pregnancy, chronic kidney⁷or, liver failure, and bone marrow disorders.⁵

Core symptoms of normocytic anemia 

Fatigue 

Fatigue is an extremely common symptom in anemia and is typically the earliest symptom to be felt by patients. The fatigue is due to the reduced number of red blood cells. Red blood cells are critical in carrying oxygen around the body. Although people with normocytic anemia have red blood cells that are the normal size, there aren’t enough of them to carry the oxygen the body needs. Red blood cells contain a protein called haemoglobin, which is key in carrying oxygen from the lungs to the rest of the body. When the number of red blood cells is low, less hemoglobin is available to transport oxygen.¹³ As a result, less oxygen reaches important parts of the body like the muscles, brain, and heart. This lack of oxygen means the body’s cells can’t produce enough energy, which can lead to symptoms like tiredness and fatigue. Because of the lack of oxygen, the body may increase respiration and heart rate as a compensatory mechanism in an attempt to circulate more oxygen.¹² Even with little physical exercise, these compensatory processes can leave a person feeling worn out and tired.⁹ Furthermore, the brain is especially vulnerable to variations in the oxygen supply. Lack of oxygen can cause a sense of brain fog, reduced awareness, and trouble concentrating, all of which add to the feeling of exhaustion.¹² Overall, several factors can lead to fatigue in people with normocytic anemia. These include reduced oxygen delivery, lower energy production, and the body working harder to compensate for the lack of red blood cells. Noticing fatigue early is important, as it can be a sign of an underlying condition, such as a chronic illness, hidden bleeding, or problems with the bone marrow, that may need further investigation and treatment.¹⁰

Pallor (Pale skin and mucous membranes)

One typical and obvious symptom of normocytic anaemia is pallor, which is essentially paleness to the skin. It is frequently one of the first things seen during a medical examination and describes a significant pallor of the skin and mucous membranes. In areas like the cheeks, palms, nail beds, and the inner eyelids, where the skin is thin and blood vessels are near the surface, this pallor is particularly noticeable.¹⁴

A drop in haemoglobin concentration is the main reason for pallor in anaemia. When haemoglobin levels fall, the skin may appear less flushed or pink. Haemoglobin is what gives blood its red hue.¹¹ Furthermore, blood is diverted from the skin to organs that have a more important role, including the heart and brain, in anaemic people. When paired with other symptoms, pallor can be an important clinical signal, but it is not used to diagnose anaemia on its own.¹⁵

Weakness 

Another characteristic sign of normocytic anaemia is weakness, which is frequently mentioned together with exhaustion. Weakness particularly refers to a loss of physical strength, as opposed to fatigue, which is more about a general lack of energy. Even when doing everyday activities like walking short distances, climbing stairs, or lifting light objects, people with anemia may find that they feel exhausted.¹⁶ The reduced oxygen transport to muscle tissues impairs their ability to operate effectively, resulting in this discomfort. To produce energy, muscles need a steady flow of oxygen, especially when exercising. Because there is low haemoglobin available to deliver oxygen, muscles in patients with normocytic anemia are more prone to become overworked and exhausted. Over time, this leads to difficulty with exercise, reduced exercise levels, and in extreme cases, there can be limitations in daily self-care tasks. 

Other clinical manifestations of normocytic anaemia 

Shortness of breath (Dyspnea)

Breathlessness is another common issue, particularly after exercising. The body reacts to low blood oxygen levels by trying to compensate by speeding up breathing. This causes the feeling of being out of breath. In people with moderate to severe anaemia, this discomfort can be felt even with minor activity, such as walking or climbing stairs.

Lightheadedness or dizziness

A decreased oxygen flow to the brain can cause lightheadedness, dizziness, or even episodes of feeling faint. This is because of sudden changes in blood pressure and a reduced blood flow to the brain, these symptoms are more likely to appear while getting up suddenly or after exerting oneself.

Headache

Headaches caused by anemia are often dull or throbbing and can last a long time. They may happen because the blood vessels in the brain widen in response to lower oxygen levels in the blood.¹⁹

Heart palpitations

The heart frequently works harder and faster to pump blood because of the decreased oxygen supply in reaction to anaemia.¹¹ Palpitations, which are more noticeable than a regular heartbeat, can be described as fluttering, racing, or hammering in the chest and may be the result of the increased effort from the heart. Although it's a strategy to help the body, it can be unsettling and cause anxiety.¹⁷

Cold feet and hands

Feeling unusually cold in your hands and feet could be due to reduced blood flow to those areas. When your body needs to prioritize, it sends more oxygen-rich blood to vital organs like the heart and brain first. This means less blood may reach your hands and feet, especially in cooler weather.

Chest pain 

In people with heart conditions or severe anemia, not getting enough oxygen to the heart can cause chest pain or discomfort, also known as angina. This can be a serious warning sign that the heart isn’t getting the oxygen it needs. It’s important to get medical help right away if this happens.¹⁷

Symptoms specific to the underlying causes 

While the general symptoms of normocytic anemia are often similar, the underlying cause can lead to additional signs that help guide diagnosis and treatment. Here are some conditions that can cause normocytic anaemia and the symptoms they would show:

Chronic Kidney Disease (CKD)

People with chronic kidney disease often develop anemia because their kidneys don’t make enough of a hormone called erythropoietin,⁵ which helps the body produce red blood cells. This type of anemia tends to come on slowly.⁸ Common symptoms include tiredness, pale skin, swelling in the legs, shortness of breath, and high blood pressure.⁷ 

Sudden blood loss

Anemia can also happen quickly if there’s sudden bleeding, such as from an injury or internal bleeding (like in the stomach or intestines). In these cases, symptoms may include a fast heartbeat, low blood pressure, cool or sweaty skin, and in more serious situations, confusion or fainting, signs that the body is going into shock.¹¹

Ongoing infections or inflammation

Anemia can also be caused by long-term infections or inflammatory conditions like rheumatoid arthritis or tuberculosis. Along with the usual signs of anemia (like fatigue and weakness), people might also experience fever, unintentional weight loss, and night sweats.²⁰

When to seek medical attention 

It’s important to speak with a healthcare provider if you experience persistent fatigue, pale skin, or unusual weakness, especially if these symptoms are affecting your ability to perform daily tasks. More urgent symptoms, such as chest pain, fainting, shortness of breath, or a rapid heartbeat, may suggest a more severe form of anemia and require immediate medical attention.²¹ Routine blood tests, including a full blood count, can help detect anemia early, even before symptoms become obvious. Early detection allows for timely treatment and helps prevent complications from underlying conditions that may be causing the anemia.²²

Summary 

Normocytic anemia can make you feel constantly tired, weak, and pale, even if your red blood cells are the right size, there just aren’t enough of them. Other common symptoms include shortness of breath, dizziness, cold hands and feet, headaches, and a racing heartbeat. These signs happen because your body isn’t getting the oxygen it needs. Spotting the symptoms early matters, since normocytic anemia is often caused by an underlying issue. If you're noticing these changes, it's important to see a healthcare provider for proper testing and treatment.