Skip to Content

Can lung problems cause leg cramps?

Leg cramps are sudden, involuntary muscle contractions that cause a tight, painful feeling in the affected muscle. They most commonly occur in the calf muscles but can also affect the feet, thighs or hands. Leg cramps often happen at night and can wake people from sleep. They usually last from a few seconds to several minutes.

Leg cramps can have various causes, ranging from overexertion and dehydration to more serious medical conditions. Some lung diseases like chronic obstructive pulmonary disease (COPD) and other respiratory conditions have also been associated with increased likelihood of leg cramps.

This article explores the connection between lung problems and leg cramps. It covers the following key questions:

What causes leg cramps?

Leg cramps can have several potential causes:

– Overuse or injury of the muscle. Using muscles more strenuously than usual through exercise or other activities can trigger cramping.

– Dehydration. Not drinking enough fluids causes electrolyte imbalances that can lead to muscle cramps.

– Pregnancy. Hormonal changes and extra weight on the body during pregnancy commonly cause leg cramping.

– Medications. Certain diuretics, statins and steroids are known to cause leg cramps as a side effect in some people.

– Poor circulation. Narrowed arteries restrict blood flow in the legs, which can cause cramps. This commonly affects people with peripheral artery disease.

– Mineral deficiencies. Being low in potassium, magnesium or calcium makes muscles prone to cramping.

– Neurological conditions. Nerve damage or disorders like motor neuron disease can increase cramping.

Why could lung diseases potentially lead to leg cramps?

There are a few reasons why having lung problems like COPD might make someone more prone to getting leg cramps:

– Low oxygen levels. Many lung diseases reduce oxygen supply in the blood. This can cause muscles to spasm and cramp.

– Medications. Drugs like bronchodilators and steroids used for treating lung disease have leg cramps as a potential side effect.

– Inactivity. People with chronic lung problems often limit their physical activity, which can increase risk of leg cramps.

– Muscle wasting. Severe or chronic respiratory disease can lead to loss of muscle mass and function, increasing cramping likelihood.

– Poor circulation. Some lung diseases may impair heart function and blood circulation, reducing oxygen delivery.

So in summary, leg cramps can stem indirectly from the effects of lung diseases through mechanisms like reduced oxygen, medications, inactivity and muscle wasting.

Are leg cramps a symptom of any lung conditions?

Chronic obstructive pulmonary disease (COPD)

Yes, leg cramps are particularly common in people with chronic obstructive pulmonary disease (COPD). COPD causes airflow limitation and breathing difficulties due to damage to the airways and lungs.

Studies show at least 30-40% of people with COPD experience leg cramps. The cramps likely result from multiple factors like low oxygen levels, reduced lung capacity, inactivity, muscle wasting, and side effects of medications used to treat COPD like bronchodilators, steroids and diuretics.


Emphysema is a type of COPD causing damage and enlargement of the lung’s air sacs, leading to shortness of breath. Given emphysema is a form of COPD, leg cramps are also a common complaint affecting around a third of patients. The inability to adequately breathe and oxygenate the blood can trigger leg muscles to cramp.

Chronic bronchitis

Chronic bronchitis involves long-term inflammation of the bronchi (airways) leading to cough and phlegm production. It is another form of COPD that restricts airflow. As with other types of COPD, chronic bronchitis suffers may experience frequent leg cramps.

Pulmonary fibrosis

Pulmonary fibrosis is a lung disease causing scarring and thickening of lung tissue, which reduces oxygen delivery to the muscles and body. Studies suggest over 20% of those with pulmonary fibrosis get leg cramps.


Pneumonia is an infection of the lungs’ air sacs that can make breathing painful and difficult. Due to high fever, dehydration, coughing and low oxygen levels, some people with pneumonia report leg cramping during the illness. The cramps tend to resolve as the infection clears.

Lung cancer

Advanced lung cancer can obstruct airways and reduce oxygenation, potentially increasing risk of leg cramping. Cramps may also result from cancer therapy side effects or paraneoplastic syndromes – rare disorders caused by substances released by some lung tumors.

Sleep apnea

Sleep apnea involves repeated pause in breathing during sleep, leading to oxygen drops that disrupt sleep. Studies show people with sleep apnea have a higher likelihood of being woken from sleep by leg cramps compared to those without the disorder.


Asthma causes swelling and narrowing of the bronchial airways, leading to breathing difficulty. While asthmatics may occasionally get leg cramps, especially when experiencing acute attacks, asthma doesn’t seem to increase overall risk compared to the general population.

So in summary, leg cramps are most strongly associated with COPD and other chronic lung diseases that impair airflow and oxygen delivery over prolonged periods. Acute respiratory infections may also increase cramping while the illness lasts.

What treatments can help leg cramps related to lung disease?

If leg cramps stem from an underlying lung condition, treating the root respiratory disorder is key. This may involve medications and therapies like:

– Bronchodilators to open constricted airways in COPD and asthma

– Inhaled steroids to reduce airway inflammation

– Supplemental oxygen administration

– Pulmonary rehabilitation programs to improve lung function and strength

– Treating infections such as pneumonia with antibiotics

– Surgery or chemotherapy in some cases of lung cancer

Improving overall leg health may also help reduce cramps:

– Calf muscle stretching before bedtime

– Regular exercise to improve circulation

– Massage to release tight calf muscles

– Hot or cold compresses on cramping muscles

– Avoiding dehydration and replenishing electrolytes

– Wearing compression stockings to improve blood flow

– Sitting with knees slightly bent to relax calf muscles before sleep

If cramps become frequent or severe, doctors may prescribe medications like:

– Quinine sulfate

– Muscle relaxants like cyclobenzaprine or baclofen

– Calcium channel blockers like diltiazem or verapamil

– Anticonvulsants like gabapentin

However, these provide only modest relief for many patients. Addressing the underlying lung disorder and leg muscle problems is key to controlling cramps long term.


Leg cramps are a common complaint for many people with chronic lung diseases like COPD, which restrict airflow and oxygenation. Reduced oxygen delivery is thought to be a key trigger for cramping by causing muscle fatigue and spasms.

Other contributing factors include deconditioning, muscle wasting, poor circulation and medications used for lung diseases. While occasional cramps may happen with infections like pneumonia, chronic respiratory conditions seem to increase risk the most.

Treatments focus on improving the underlying lung condition with measures like bronchodilators, steroids, oxygen therapy and rehabilitation. Stretching, exercise, massage and compression stockings can also help reduce leg cramps. Medications for cramp relief have limited efficacy. Getting to the root causes in the lungs and leg muscles provides the best results.

Lung disease Leg cramp frequency
Chronic obstructive pulmonary disease (COPD) 30-40% affected
Emphysema ~30% affected
Chronic bronchitis Likely high frequency
Pulmonary fibrosis >20% affected
Pneumonia Temporary during illness
Lung cancer Possibility in advanced stages
Sleep apnea Higher likelihood
Asthma No clear increase


1. American Academy of Family Physicians. Leg cramps at night. Updated March 2020. Accessed February 12, 2023.

2. Garrison SR, D’Alonzo GE. Skeletal muscle abnormalities in pulmonary arterial hypertension. J Appl Physiol (1985). 2012;113(7):1046-1051. doi:10.1152/japplphysiol.00436.2012

3. Maltais F, Decramer M, Casaburi R, et al. An official American Thoracic Society/European Respiratory Society statement: update on limb muscle dysfunction in chronic obstructive pulmonary disease. Am J Respir Crit Care Med. 2014;189(9):e15-e62. doi:10.1164/rccm.201402-0373ST

4. Morton A, Landers G, Sprogis A, Reyes AL, Dunn D, Tran ZV. Leg cramp frequency in patients with pulmonary fibrosis. Respir Med. 2019;152:64-70. doi:10.1016/j.rmed.2019.05.015

5. Oliveira MM, Oliveira Júnior AD, et al. Muscle dysfunction in COPD: systemic effect or deconditioning? COPD. 2017;14(5):529-536. doi:10.1080/15412555.2017.1337754

6. Stillwell SB, Fineout-Overhold E, Melnyk BM, Williamson KM. Evidence-based practice, step by step: asking the clinical question: a key step in evidence-based practice. Am J Nurs. 2010;110(3):58-61. doi:10.1097/01.NAJ.0000368959.11129.79