Paroxysmal Nocturnal Hemoglobinuria (PNH)

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare blood disorder characterized by the premature breakdown of red blood cells. It can express variably in patients, from unnoticeable or minor symptoms to severe symptoms with multiple complications.1 

What is Paroxysmal Nocturnal Hemoglobinuria?

Paroxysmal means “occurring in bouts or episodes.” While the breakdown of red blood cells occurs constantly in people with PNH, certain triggers may increase this breakdown. Typically, periods of stress, such as infection, injury, trauma, surgery, or emotional upset, increase inflammation in the body and can worsen the breakdown of red blood cells by the immune system.1

Nocturnal means “occurring at night.” This refers to the tendency of hemoglobinuria  — one of the main visible signs of PNH — to occur at night or first thing in the morning. While the breakdown of red blood cells occurs both day and night, the byproducts from this breakdown have time to collect in the bladder overnight. The increased concentration of these byproducts, namely hemoglobin, allows them to become more visible in the initial urination after a sustained sleep. This urine appears more reddish, brownish, or dark in color in around 1 in every 4 people with PNH.1 

The word “hemoglobinuria” can be broken down into “hemo” meaning “blood,” “globin” referring to a type of protein in the blood, and “uria” meaning urine. This means that there is hemoglobin, a protein found in the blood, in the urine. Hemoglobin is released into the blood when the immune system breaks down red blood cells. This excess free hemoglobin is collected and excreted from the body as waste through the urine.1

Managing Disease Symptoms and Treatment Side Effects

Patients may experience a wide range of symptoms due to PNH. One of the biggest symptoms that may interfere with daily living is fatigue, which results from the anemia caused by PNH. Learning to prioritize and do the most important things first can help people with PNH to conserve their energy.1

Asking family and friends for help and support with daily tasks, especially when undergoing treatment, may decrease stress and worries for people with PNH. This support can even improve disease management, as stress, both physical and emotional, can trigger or exacerbate periods of hemolysis.1

People with PNH may want to talk to their employers about how PNH symptoms affect their job. Employers may be able to grant work accommodations for attending treatment appointments and for making their daily work tasks easier and less energy-consuming.1 

Many different treatments are available for people with PNH, including2

  • Empaveli™ (pegcetacoplan), Ultomiris® (ravulizumab), and Soliris® (eculizumab)
  • Bone marrow transplantation
  • Medications to thin the blood to prevent clots (anticoagulant therapy)
  • Corticosteroids to reduce inflammation

Keeping a diary of symptoms and side effects, especially after beginning any new medications, may be helpful to the medical team, including a hematologist, a general practitioner, and specialized nurses, who provide care for people with PNH. With this detailed information, doctors and the medical team can better guide people with PNH in ways to manage their symptoms and side effects, including coping mechanisms, supplementation, additional medications, or lifestyle adaptations.1

Read more about PNH signs and symptoms

Managing Emotions After Diagnosis

Getting a diagnosis of PNH may cause people to feel a range of emotions, from stress to worry to anger. These emotions can also impact disease activity. Stress is a trigger that may worsen the symptoms of PNH. It is important to find ways to manage these emotions, such as seeking professional counselling.1 

Complementary therapies, such as aromatherapy, massage therapy, visualization techniques, and meditation and relaxation techniques may promote emotional wellbeing and reduce the stress and anxiety that a diagnosis of PNH might cause.1

Read more about PNH diagnosis

Sleep Recommendations

It is recommended that people with PNH avoid sleeping during the day to maintain regular sleeping patterns. Improving sleep quality can also decrease stress and improve disease management. Recommendations for improving sleep include: regular light physical exercise, meditation and relaxation techniques, avoiding caffeinated drinks and alcohol, listening to music or reading in the evening, and taking a warm bath right before bed.1 

Lifestyle Recommendations


Physical activity is important for both the body and mind. Exercises may range from light passive exercises, gentle walking, or light housework to more intense activities such as cycling or running. Medical teams can advise exercise routines based on each person’s unique case and risks.1 Activity modifications may be required, such as increased rest breaks, to accommodate for symptoms of anemia, such as fatigue and shortness of breath with exertion.

Diet and Nutrition

Healthy diets are recommended for people with chronic illnesses such as PNH. This includes the avoidance of chemicals and sugars that may impact the body’s function and a focus on eating a balanced, nutritious diet to help the body to function better. It is also important for patients to stay hydrated by drinking plenty of water.1

Read more about PNH diet and nutrition

Care Team

It is important to recognize that certain events, such as surgery or pregnancy, may worsen PNH symptoms by increasing the breakdown of red blood cells and may increase the risk of blood clots, which is already higher in people with PNH. Consulting with specialists such as high-risk obstetricians, gynecologists, or hematologists prior to getting pregnant or having surgery is recommended to help prepare for these events while minimizing risks.1 

Read more about PNH surgical management

Patient Resources

Organizations such as PNH Source, OneSource from Alexion (the company that manufactures Ultomiris), the National Organization for Rare Diseases (NORD), and the Aplastic Anemia and Myelodysplastic Syndrome International Foundation (AAMDS International Foundation) provide community support, patient and caregiver educational materials, patient advocacy, and information on current PNH research and clinical trials.3 


  1. Understanding PNH. The Nurses Group of the European Society for Blood and Marrow Transplantation (EBMT NG). Updated October 2015. Accessed December 1, 2022.
  2. Besa EC. Paroxysmal nocturnal hemoglobinuria treatment & management: approach considerations. Medscape. Updated May 20, 2021. Accessed December 1, 2022.
  3. PNH resources. PNH Source. Accessed December 1, 2022.

Reviewed by Debjyoti Talukdar, MD, on 11/30/2022.