Nocturnal leg cramps are sudden spasms in the lower leg and foot muscles. The calf muscles are most often involved. The cramps are painful and often disrupt sleep.
The Calf Muscles
Copyright © Nucleus Medical Media, Inc.
The exact cause of nocturnal leg cramps is unknown. They may be due to chemical imbalances. This may lead to problems with the nerves, muscles, or blood supply.
Nocturnal leg cramps are more common in people aged 50 years and older. Other things that raise the risk are:
The main symptom is a sudden cramp in the calf or foot muscle.
The doctor will ask about symptoms and health history. A physical exam will be done. Diagnosis is based on symptoms.
Blood tests and imaging tests may be done to check for underlying causes.
The goal of treatment is to reduce cramps. It may also include treating any underlying causes.
If no cause is found, treatment options are:
Medicines may be used if the cramps are severe. Options are:
The risk of nocturnal leg cramps may be reduced by:
Family Doctor—American Academy of Family Physicians
Ortho Info—American Academy of Orthopaedic Surgeons
The College of Family Physicians of Canada
Women's Health Matters
Delacour C, Chambe J, et al. Association between physical activity and nocturnal leg cramps in patients over 60 years old: a case-control study. Sci Rep. 2020;10(1):2638.
Nocturnal leg cramps. EBSCO DynaMed Plus website. Available at: https://www.dynamed.com/condition/nocturnal-leg-cramps. Accessed February 16, 2021.
Roguin Maor N, Alperin M, et al. Effect of magnesium oxide supplementation on nocturnal leg cramps: a randomized clinical trial. JAMA Intern Med. 2017;177(5):617-623.
Last reviewed January 2021 by Mary Beth Seymour, RN
Last Updated: 2/16/2021