What You Need to Know About Leg Cramps

Leg cramps occur when muscles in the leg involuntarily contract, becoming tight and painful. While leg cramps usually occur in the calf muscle, they can affect any part of the leg, including the feet and thighs.

Although they are generally harmless, leg cramps can be extremely painful, lasting anywhere from a few seconds up to 10 minutes. After the cramping has passed, the leg may continue to be painful and tender for several hours.

While leg cramps can occur at any time of the day, three out of four cases occur at night during sleep*. If you suffer from leg cramps in bed, calf cramps or foot cramps, there are ways to prevent and treat them. To do that though, it’s important to work out where the problem stems from.

leg cramps

What causes leg cramps?

Finding out what causes cramps – whether that’s cramps in legs, cramps in calves or cramps in feet – can make it easier to treat them, and sometimes, prevent them altogether. In many cases, leg cramps can occur for no apparent reason. These are known as idiopathic leg cramps.

Leg cramps can also occur as a symptom or complication of a health condition. These are known as secondary leg cramps. Leg cramps during pregnancy are common, but muscle cramps can also be caused by certain types of medication, exercise and liver disease.

When it comes to idiopathic leg cramps, there are a number of theories regarding possible causes. These can include:

  • Abnormal nerve activity during sleep, causing the muscle of the leg to cramp.
  • An abrupt restriction of blood supply to the affected muscles in the leg.
  • Extreme strain being placed on the leg muscles, as can happen during exercise.
  • Age can also play a role, as tendons shorten as a person gets older. Because tendons connect muscles to bone, when they become too short, they may cause muscles to cramp**.

Looking more closely at secondary leg cramps caused by an underlying condition or another identifiable cause, these can be linked to the following:

  • Neurological conditions, such as motor neurone disease or peripheral neuropathy
  • Liver disease (when the liver stops working properly, toxins build up in the blood, which may cause muscles to go into spasm)
  • Pregnancy (the extra weight of pregnancy can put strain on the leg muscles, making pregnancy leg cramps more common)
  • Infection, such as tetanus
  • Dehydration (when the body becomes dehydrated, salt levels can drop, which may trigger muscle cramps)
  • Medication, such as diuretics, statins, raloxifene, nicotinic acid and nifedipine
  • Toxins, such as lead and mercury
  • Low blood levels of calcium, magnesium or potassium

How do you stop leg cramps?

Having looked at what causes leg cramps and possible muscle cramps causes, it’s now time to investigate how to stop cramps, with a focus on how to prevent them occurring.

  • Exercise: If you suffer from leg cramps at night, you may find exercising during the day will reduce the number of cramping episodes you experience.
  • Stretching: Regular stretching of the affected muscles may also help prevent cramps, or reduce their frequency. Try stretching your legs before bed each night, by standing with the front half of your feet on a step, then slowly lowering your heels until they are below the level of the step. Hold for a few seconds, lift back up and repeat.
  • Positioning: If you sleep on your back, prop your feet against a pillow to keep your toes pointing upwards. If you sleep on your front, hang your feet over the end of the bed to keep them in a relaxed position, discouraging your calf muscles from tensing and contracting.
  • Treatment of the Underlying Cause: If you suffer from secondary leg cramps, you may need to treat the underlying cause to reduce leg cramping episodes. In terms of leg cramps during pregnancy, these should stop after the baby is born. If you are unable to treat the underlying cause, for example, as a result of liver disease, medications such as muscle relaxants may be required.
  • Medication: When leg cramps are severe and do not respond to stretching and exercise, medication may be required.
  • Painkillers: Painkillers can be used to treat pain that persists after leg cramping, such as paracetamol or ibuprofen.
  • Quinine: Originally designed to treat malaria, quinine has also been found to be effective in reducing the number of leg cramps experienced. Take note, quinine can have unpleasant side effects***.
  • Other treatments can include having a hot bath, with or without Epsom salts, staying hydrated and taking magnesium supplements****.

When should you seek medical advice for leg cramps?

If leg cramps are affecting your quality of life, seriously interfering with your sleep so that you are unable to function properly the following day, a trip to the GP may be required.

If your cramps last longer than 10 minutes and do not improve, despite walking around and stretching, or if cramps develop after you come into contact with toxic substances, you should seek immediate medical help.

 

* https://www.nhsinform.scot/illnesses-and-conditions/muscle-bone-and-joints/conditions/leg-cramps#introduction

** https://www.nhsinform.scot/illnesses-and-conditions/muscle-bone-and-joints/conditions/leg-cramps#causes

*** https://www.nhsinform.scot/illnesses-and-conditions/muscle-bone-and-joints/conditions/leg-cramps#treatment

**** https://www.healthline.com/health/pain-relief/how-to-stop-leg-muscle-cramps