Sickle Cell Anemia Symptoms

Sickle cell anemia refers to a group of genetic blood disorders that affect a person’s levels of hemoglobin, the protein in red blood cells that transports oxygen. Sickle cell anemia causes a person’s red blood cells to become sickle-shaped rather than disc-shaped, which can result in pain, breathing difficulties, and other complications.
Symptoms of Sickle Cell Anemia
- Legs
- Arms
- Chest
- Back
Pain may be accompanied by tenderness, swelling, and redness over the area of the blocked blood flow.
Some people can treat sickle cell crises at home with rest, pain relievers, and hydration, while others require hospitalization and measures like intravenous (IV) fluids, oxygen therapy, and strong pain medication.
- A racing or irregular heartbeat
- A yellow tint to the skin and whites of the eyes, known as jaundice
- Cold hands and feet
- Confusion
- Urine that's darker than usual
- Difficulty concentrating
- Headache
- Insomnia
- Leg cramps
- Pale skin
- Shortness of breath, particularly with exercise
- Weakness or decreased stamina
- Fatigue
- Severe weakness
- Breathlessness
- Extremely rapid heart rate
A physician with special training in blood disorders, known as a hematologist, can identify the best way to manage the anemia associated with sickle cell anemia.
Types of Sickle Cell Disease
- Hemoglobin SS (HbSS) Around 65 percent of people with sickle cell disease have HbSS, a severe type. People with HbSS inherit an abnormal gene connected to hemoglobin production, hemoglobin S, from both parents. This affects almost all hemoglobin and leads to chronic anemia. When doctors use the term “sickle cell anemia,” they are often referring to HbSS.
- Hemoglobin SC (HbSC) About 1 in 4 people with sickle cell disease have HbSC, which is mild to moderate. It develops when a person inherits a hemoglobin S gene from only one parent and a hemoglobin C gene, a different faulty type, from the other.
- Hemoglobin (HbS) Beta Thalassemia Plus (Beta +) People with HbS beta + have a hemoglobin S gene from one parent and an abnormal gene known as beta thalassemia from the other. People with this type of HbS beta thalassemia generally have mild symptoms, and around 8 in every 100 people living with sickle cell disease have HbS beta +.
- Hemoglobin (HbS) beta thalassemia zero (beta 0) This type of hemoglobin beta thalassemia occurs in around 2 of every 100 people with sickle cell disease and causes severe symptoms similar to HbSS. Doctors also use the term “sickle cell anemia” to refer to HbS beta 0.
Other rare types involve different gene changes, including:
- Hemoglobin SD
- Hemoglobin SE
- Hemoglobin SO
Potential Complications of Sickle Cell Anemia
Sickle cell anemia can cause a wide range of sudden and severe complications when sickled cells block blood vessels.
- A long-lasting, painful erection: If sickled cells build up in your penis, it can cause an ongoing erection that causes pain, also known as priapism. If this lasts for four hours or longer, seek emergency care immediately.
- Acute chest syndrome: This life-threatening sickle cell anemia complication occurs when sickled cells block oxygen-rich blood from the lungs. It can injure the lungs, cause breathlessness, and reduce the body’s oxygen supply.
- Avascular necrosis: If sickled cells block the blood supply to the bones, the tissue may die, and joints can narrow. This most often affects the hip in people with sickle cell anemia.
- Blood clots: Sickled cells have a higher chance of forming blood clots than healthy cells, meaning the clots can lodge in a deep vein or a lung. These can cause severe illness or death.
- Chronic pain: People with chronic pain due to sickle cell anemia may feel it for longer than six months.
- Eye problems: Altered red blood cells can block blood vessels in the eye, often in the light-detecting layer of cells at the back of the eye known as the retina. This can lead to sudden and severe vision loss, possibly causing blindness.
- Gallstones: Bilirubin is a pigment the body produces during the breakdown of red blood cells. The bodies of people with sickle cell anemia break down cells faster, which can lead to a buildup of bilirubin. This can cause gallstones that may block the gallbladder.
- Infections: Sickled cells can affect how the spleen works. As this is a key part of the immune system’s defense against infections, sickle cell crises may increase a person’s risk of life-threatening bacterial infections.
- Organ failure: Blocked blood and oxygen supply can damage the kidneys, heart, and other organs, sometimes leading to organ failure.
- Pulmonary hypertension: High blood pressure in the lungs can lead to breathlessness and fatigue for people with sickle cell anemia, and it can be fatal. This is most common in adults with the condition.
- Splenic sequestration: Mostly before 6 years of age, children may experience a potentially life-threatening splenic sequestration crisis in which sickle cells block the narrow blood vessels of the spleen, causing belly pain, an enlarged spleen, pale skin, and a rapid heartbeat.
- Stroke: Sickled cells can block blood vessels that feed the brain with oxygen, reducing your brain’s access to oxygen. This can cause a stroke for around 1 in 10 people with sickle cell anemia.
When to See a Doctor
- A fever of 101.5 degrees F (38.5 degrees C), especially in children, who have a higher risk of infection than adults
- Paralysis or weakness on one side of the arms, legs, or face
- Chest pain and coughing
- Confusion
- Problems while walking or speaking
- Sudden vision loss
- Numbness without explanation
- A severe headache
- A painful erection lasting longer than four hours
During some crises, drinking plenty of fluids and taking nonsteroidal anti-inflammatory drugs (NSAIDs) may help to manage the pain. But if pain management is not possible, a hospital may be able to provide more effective pain relief.
The Takeaway
- Sickle cell anemia is the most severe type of sickle cell disease, causing anemia symptoms, pain crises, jaundice, and swelling of the hands and feet.
- Some symptoms may resemble those of other types of hemolytic anemia, and the complications can affect many organs, vision, breathing, and sexual function.
- If the pain is hard to tolerate or manage and you have concerns about whether symptoms may result from sickle cell anemia, a doctor's visit is the best way to rule out other health problems and seek effective treatment.
Resources We Trust
- Cleveland Clinic: Sickle Cell Disease
- Nemours TeensHealth: Acute Sickle Cell Pain
- National Heart, Lung, and Blood Institute: Living With Sickle Cell Disease
- National Academies Press: Addressing Sickle Cell Disease: A Strategic Plan and Blueprint for Action
- American Sickle Cell Anemia Association: Reach Out to Sickle Cell Support Groups

Nimit Sudan, MD
Medical Reviewer
Nimit Sudan, MD, is a hematologist and medical oncologist with UCLA. He is an assistant clinical professor at UCLA and serves as a lead physician at the Encino community practice. He has a special interest in integrative medicine and oncology.
Dr. Sudan provides comprehensive care for adult patients with all types of hematologic and oncologic conditions. His mission is to treat every patient with the utmost compassion and care, and to develop a strong doctor-patient relationship. He is passionate about patient and family education, and educating larger communities on cancer awareness and prevention. He also has a special interest in integrative medicine, and is certified in acupuncture.
Sudan is from the Midwest, and received both his medical degree and bachelor's degree from Wayne State University in Detroit, Michigan. He completed his internal medicine residency at the Cleveland Clinic Foundation, and his hematology/oncology fellowship at Western Pennsylvania Hospital in Pittsburgh.

Adam Felman
Author
As a hearing aid user and hearing loss advocate, Adam greatly values content that illuminates invisible disabilities. (He's also a music producer and loves the opportunity to explore the junction at which hearing loss and music collide head-on.)
In his spare time, Adam enjoys running along Worthing seafront, hanging out with his rescue dog, Maggie, and performing loop artistry for disgruntled-looking rooms of 10 people or less.
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