Sickle Cell Disease Crisis Triggers

Triggers for Sickle Cell Disease Crisis

Triggers for Sickle Cell Disease Crisis
iStock; Everyday Health
Sickle cell disease (SCD) is a group of blood disorders that affect your red blood cells, which carry oxygen throughout your body. A sickle cell crisis happens when your red blood cells get sticky and harden into a C shape instead of their normal round shape.

When these cells change, it causes severe pain — the main symptom of a sickle cell crisis. This pain can start anywhere, but usually affects the back, chest, arms, or legs.

Several common triggers can lead to sickle cell crisis, and by understanding these triggers, you can lower your risk.

 Below, learn more about what happens during a sickle cell crisis, triggers to watch for, and how you can avoid them.

What Is a Sickle Cell Disease Crisis?

During a sickle cell crisis, sticky, stiff hemoglobin cells cling to the walls of your blood vessels. As more and more cells get stuck, they can slow down or even block blood flow in some areas.

You feel severe pain in a sickle cell crisis because your blood can’t carry oxygen to the blocked areas, and pain is your body’s response.

 This pain can happen suddenly and last anywhere from a few hours to several days.

“It is the worst pain you’ve ever experienced in your life,” says Jeffrey Woodson, who has lived with sickle cell disease for many years in St. Louis. “At its worst, it feels like every bone in your body is broken as you’re trying to move around — like a dagger slowly being driven into every muscle and bone in your body.”

Pain is a short-term effect of these crises. But long-term blood flow blockage in different parts of the body can cause complications like:

  • Acute chest syndrome: A pneumonia-like illness
  • Blood clots: When sickled red blood cells stick together
  • Chronic pain: Pain that lasts longer than six months

  • Spleen complications: Swollen spleen with left-sided abdominal pain

  • Leg ulcers: Open wounds from blocked blood flow

  • Liver disease: Can include liver damage and gallstones

  • Necrosis: Bone or tissue death
  • Painful erections: Can last four hours or more

  • Stroke: Blood flow blockage that causes brain damage

Common Sickle Cell Crisis Triggers

Some activities and situations can trigger a sickle cell crisis. You may not always be able to prevent crises, but knowing possible triggers can help you avoid them.

Dehydration

When you don’t drink enough water, your blood vessels have less fluid in them, which can make it easier for a sickle cell crisis to start.

Dehydration is Woodson’s number one trigger. “The more I can stay hydrated, the better chances I have of not setting off a pain episode,” he says.

People with sickle cell disease lose water more easily because their kidneys aren’t as efficient, says Crawford Strunk, MD, a hematologist at Cleveland Clinic and the codirector of the Sickle Cell Medical Neighborhood, a lifespan sickle cell comprehensive center in Ohio. “So especially in hot weather, they need to make sure that they're staying appropriately hydrated,” says Dr. Strunk.

Extreme Temperatures

Extreme temperatures — both cold and hot — can trigger a sickle cell crisis.

When you get cold, your blood vessels narrow, which can slow down blood flow and make it easier for sickled cells to get stuck. And staying in a hot environment can lead to dehydration.

“Without fail, being cold and wet is an automatic ‘I’m going to have a real bad episode’ situation,” says Woodson, who rarely goes swimming during the summers, even on extremely hot days.

“Even if the pool is heated, and it’s been hot for several days, I am extremely cautious because a small gust of wind as I’m coming out of the pool or walking into air-conditioning can become problematic,” says Woodson.

Sudden shifts in weather can also prompt a crisis, says Strunk. “The change in temperature is what really drives it.”

High Altitudes

When you visit a high-altitude location (including traveling by airplane), your body has to adjust to the lower amount of oxygen in the air.

 Low oxygen levels can prompt blood cells to sickle.

Physical and Emotional Stress

Overexertion and overtiredness can be a big issue, says Strunk. Mental and emotional stress and high-intensity physical activity can all trigger sickle cell crises.

Poor Sleep

Lack of sleep may also create the right conditions for a sickle cell crisis. In one study of 53 teenagers with SCD, poor sleep was connected to increased pain and other complications.

Infections

Sickness can be a crisis trigger, says Strunk. “Colds, flus, anything that's going to stimulate your immune response is going to overdrive your sickle cell disease as well.”

How to Avoid Sickle Cell Crisis Triggers

Once you learn your sickle cell crisis triggers, you can take steps to avoid them and prevent a crisis.

Stay hydrated. Ask your doctor how much water you should drink every day. Then, meet that goal by setting reminders to drink, bringing a water bottle with you everywhere, and including water-rich snacks in your diet, like watermelon and strawberries.

 Also avoid alcohol, which can cause dehydration.

Dress for the weather. Dress in layers so you can regulate your temperature easily during the day. You have to plan for changing weather, especially in spring and fall, when temperatures can fluctuate, says Strunk.

Avoid sudden temperature changes. If you go swimming, get in the water slowly and dry off immediately when you get out.

Pace yourself. When you plan on being physically active, build in plenty of rest breaks and stop if you feel tired.

Get good sleep. Maximize your sleep by following healthy sleep habits. Keep a consistent sleep schedule, create a calming bedtime routine, and make your sleeping space cool, dark, quiet, and comfortable.

Manage stress. Use mindfulness techniques like deep breathing, meditation, and progressive relaxation to calm your body and reduce stress.

Get regular medical care. See your hematologist for checkups regularly (usually every 3 to 12 months), and get recommended vaccinations for illnesses like flu, COVID-19, pneumonia, and meningococcal disease.

Take your medications. If you take hydroxyurea or other medicines to treat sickle cell, be sure to take them as prescribed.

Prevent infection Wash your hands often to lower your risk of an infection.

You may not always know your triggers, but over time, you'll start to recognize them, says Strunk.

“It wasn’t until I was having more frequent episodes that I started taking inventory and noticing what was triggering me,” says Woodson.

How to Manage a Crisis

How you manage a sickle cell crisis depends on how severe your symptoms are and where in your body you feel them.

“Since there are levels to an episode, some actions can trigger small episodes in a specific area, and if caught early enough with pain meds, hydration, and heating pads, it won’t last long and won’t spread to other areas of my body,” says Woodson.

If you feel sickle cell pain coming on, use these tips at home to manage it:

  • Drink plenty of water.
  • Massage painful areas.
  • Take over-the-counter medications approved by your hematologist, like acetaminophen (Tylenol) or ibuprofen (Advil).
  • Place a warm pack on the painful area or take a hot bath. (Never use cold packs or ice to relieve pain.)
Call your doctor or visit your nearest emergency room if you experience these symptoms:

  • High fever
  • Trouble breathing
  • Pain that doesn’t improve with treatment at home
  • Severe vomiting or diarrhea
  • Headache or dizziness
  • Pale skin or lips
  • An erection lasting over two hours
  • Seizures
  • Confusion or slurred speech
  • Abdominal swelling that happens quickly
  • Vision changes
  • One-sided weakness
If you need care in the hospital, your health team may give you medications, blood transfusions, or other treatments.

One major struggle people with SCD report is facing stigma and bias when they go to the ER with severe pain, says Strunk. (Opioid and non-opioid pain relievers may be used to treat a crisis in an emergency setting).

 “But when you look at the data nationwide, there's very little evidence that suggests that the risks and rate of opioid use disorder is higher in sickle cell patients than it is in the rest of the country.”
Before you have a pain crisis, make a pain management plan with your hematologist and ask for a paper copy. Then, when you need to go in for stronger pain management, you can show that document, which should help any provider get familiar with your needs much faster.

You can also ask your hematologist where you should go in case of a severe crisis. Some outpatient acute care centers or infusion centers have specialized teams better able to care for someone with sickle cell.

The Takeaway

  • A sickle cell crisis happens when red blood cells get stiff and sticky and block blood flow to parts of your body, causing severe pain.
  • Sickle cell crisis triggers can include dehydration, sudden temperature changes, high altitudes, stress, poor sleep, and illness.
  • Once you learn your specific triggers, you can try to avoid them, but if you do have a crisis, you can manage it with approved medication, warm packs, and help from your provider.

Resources We Trust

EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
Resources
  1. About Sickle Cell Disease. Centers for Disease Control and Prevention. February 21, 2025.
  2. Borhade MB et al. Sickle Cell Crisis. StatPearls. February 25, 2024.
  3. Sickle Cell Crisis. Cleveland Clinic. August 29, 2024.
  4. Sickle Cell Disease: Causes and Risk Factors. National Heart, Lung, and Blood Institute. August 20, 2024.
  5. Complications of SCD: Pain. Centers for Disease Control and Prevention. May 15, 2024.
  6. Complications of SCD: Splenic Sequestration. Centers for Disease Control and Prevention. May 15, 2024.
  7. Complications of SCD: Leg Ulcers. Centers for Disease Control and Prevention. May 15, 2024.
  8. Complications of SCD: Liver Problems. Centers for Disease Control and Prevention. May 15, 2024.
  9. Complications of SCD: Priapism (Painful Erection of the Penis). Centers for Disease Control and Prevention. May 15, 2024.
  10. Living with Sickle Cell Disease – Triggers. Alder Hey Children's NHS Foundation Trust. August 13, 2024.
  11. Hackett PH et al. High-Altitude Travel and Altitude Illness. Centers for Disease Control and Prevention. April 23, 2025.
  12. Obadina M et al. High-Altitude Hypoxia Is Common in Adults with Sickle Cell Disease. Blood. November 2, 2023.
  13. Valrie CR et al. Sleep Problem Risk for Adolescents with Sickle Cell Disease: Socio-demographic, Physical, and Disease-Related Correlates. Journal of Pediatric Hematology/Oncology. March 2018.
  14. Britts R. Essential Guide to Caring for Someone with Sickle Cell Disease. Sickle Cell Association.
  15. Water: How Much Should You Drink Every Day? Mayo Clinic. January 21, 2026.
  16. Living With: Sickle Cell Disease. National Health Service. November 30, 2022.
  17. Sleep Deprivation and Deficiency: Healthy Sleep Habits. National Heart, Lung, and Blood Institute. March 24, 2022.
  18. 5 Things To Know About Relaxation Techniques for Stress. National Center for Complementary and Integrative Health. April 30, 2026.
  19. Sickle Cell Disease: Living With Sickle Cell Disease. National Heart, Lung, and Blood Institute. August 22, 2024.
  20. Arzoun H et al. Opioid Use in Patients With Sickle Cell Disease During a Vaso-Occlusive Crisis: A Systematic Review. Cureus. January 21, 2022.
  21. Steps to Better Health Toolkit: Managing Acute Pain. Centers for Disease Control and Prevention. May 15, 2024.
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Walter Tsang, MD

Medical Reviewer
Walter Tsang, MD, is a board-certified medical oncologist, hematologist, and lifestyle medicine specialist. Inspired by the ancient Eastern philosophy of yang sheng ("nourishing li...

Abby McCoy, RN

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Abby McCoy is an experienced registered nurse who has worked with adults and pediatric patients encompassing trauma, orthopedics, home care, transplant, and case management. She is...