NOCTURNAL LEG CRAMPS
What are nocturnal leg cramps?
A leg cramp is the painful sensation caused when a muscle involuntarily contracts too hard. This involuntary contraction is called a spasm. It most often occurs in a calf muscle, below and behind a knee. The small muscles of the feet are sometimes affected.
A cramp pain typically lasts a few minutes. In some cases it lasts just seconds, but in some cases it lasts up to 10 minutes. The severity of the pain varies. The muscle may remain tender for up to 24 hours after a leg cramp.
Nocturnal leg cramps usually occur when we are in bed lying flat with our feet partially downward flexed. They can become a distressing condition if our sleep is regularly disturbed. In severe cases this leads to secondary insomnia, sleep deprivation, and impaired function during the day.
Who gets leg cramps?
While many people have an occasional nocturnal leg cramp, they become more common as we age. About 1 in 3 people over the age of 60, and about half of people over the age of 80, have regular leg cramps. About 4 in 10 people who have leg cramps have at least three per week. They occur every day in some people.
What causes nocturnal leg cramps?
Unknown cause (idiopathic leg cramps)
One theory is that cramps occur when a muscle that is already in a shortened position is stimulated to contract. As the muscle is already shortened, to contract further may cause the muscle to go into spasm. This commonly happens at night in bed as the natural position we lie in is with the knees slightly bent (flexed), and with feet pointing slightly downwards. In this position the calf muscle is relatively shortened and may be prone to cramps. This theory explains why stretching exercises may cure the problem.
In some cases, the cramps may be a symptom of another condition or problem. For example:
- Some drugs can cause cramps as a side-effect, or make cramps occur more often. These include: diuretics (‘water tablets’), nifedipine, cimetidine, salbutamol, statins, terbutaline, lithium, clofibrate, penicillamine, phenothiazines, and nicotinic acid.
- Over-exertion of muscles.
- Conditions that cause alterations in the balance of salts in the bloodstream (such as a high or low sodium or potassium level).
- Some people who have kidney disease and are on dialysis get leg cramps.
- Pregnancy – usually in the later stages.[
- An untreated under-active thyroid gland.
- Peripheral vascular disease (narrowing of the leg arteries which causes poor circulation).
- Excess alcohol.
- Some uncommon disorders of nerves.
- Rare causes include: cirrhosis of the liver; lead poisoning; sarcoidosis.
- and of course, venous insufficiency.
With the above conditions the cramps would just be one of various other symptoms. Therefore, if you are otherwise well, and have no other unexplained symptoms, then the leg cramps are likely to be idiopathic (unknown cause) and not due to a secondary cause.
What is the treatment for a leg cramp?
Stretching and massaging the affected muscle can usually relieve an attack of cramp. Most cramps soon ease off. Painkillers are not usually helpful as they do not act quickly enough. However, a painkiller such as acetaminophen or ibuprofen may help to ease muscle discomfort and tenderness that sometimes persists for up to 24 hours after a cramp has gone.
What are the options for preventing leg cramps?
If cramps do not occur often, then no particular treatment is usually needed. However, if you have frequent cramps, you may wish to consider ways of preventing them.
Consider your medication (where appropriate) or other conditions
Tell your doctor if you take any of the drugs listed earlier. It may be causing the leg cramps, or making them recur more often. Alternative drugs may be available. Also, if you have other symptoms apart from cramps, see your doctor who may examine you or do some checks to rule out a secondary cause for the cramps.
Stretching exercises are commonly advised. However, there is a lack of good research evidence to prove that they work. One research study concluded that stretching exercises did reduce the number and severity of cramps, but another study did not confirm this. However, many doctors feel that regular calf stretching does help. So, as it may help, it is worth trying if you are able to do the exercises. If it works, you will not need any tablets to prevent the cramps.
At first, do stretching exercises of affected muscles for about five minutes, three times a day. Do the last exercise shortly before bedtime. If the cramps ease off, you may then only need to do the exercise once or twice a day to keep the cramps away.
To stretch calf muscles, stand about 60-90 cm from a wall. Then, keeping the soles of your feet flat on the floor, bend forward and lean on the wall. You will feel your calf muscles stretch. Do this several times, each time for as long as you can manage. It may take a week or so of exercises before you notice an improvement. So, it is worth giving yourself a 2-4 week trial of regular calf stretching exercises to see if your cramps ease off. The cramps may not go completely, but their frequency and/or severity may reduce.
Posture of the legs when resting in bed
Positions which prevent the calf muscle from shortening when you are asleep may help. The following are not proven treatments (from research studies), but some experts believe that they help to prevent cramps.
- Using a pillow to prop the feet up in bed while sleeping on your back.
- Hanging the feet over the end of the bed while sleeping on your front.
- Keeping blankets loose at the foot of the bed to prevent toes and feet from pointing downwards during sleep.
- In severe cases, a posterior splint to keep the calf muscle on stretch to keep the calf muscle from stretching might be needed.
Medications and Supplements for Leg Cramps
Scientific (and not so scientific) studies evaluating various medications and supplements advocated for the treatment and prevention of leg cramps have produced mixed and unreliable results.
The FDA has banned quinine for the use of nocturnal leg cramps because of many complications with quinine.
Other popular remedies include:
Potassium Chelate 99 mg at night.
Magnesium Orotate: 200 to 400 mg at night
Vitamin E: 400 mg at night
Apple cider vinegar and honey: 2-3 tablespoons of apple cider vinegar and 1 tablespoon of honey in an 8 oz glass of water. (This may work by affecting calcium levels in muscles.)
Pickle juice (high in sodium)
An important element in nocturnal night cramps may be dehydration. Alcohol and caffeine can significantly increase dehydration. Drinking enough water daily (8 glasses) may help prevent dehydration.
Other Leg Pain or Discomfort Problems
Like many problems in medicine, leg pain can be multifactorial. The Alaska Vein Clinic and Dr. Artwohl will not rush to diagnose every problem as a vein issue, but carefully consider all possibilities and then discuss with you whether all or part of your leg pain can be helped by treating the underlying vein disorder.
Signs and Symptoms:
Condition that may be causing it:
Aching or deep pain brought on by walking or other exercise and relieved by rest:
Poor arterial circulation. These cramps may be caused when the circulation blocked and the arteries cannot increase the oxygen supply for required for muscle activity.
Aching deep pain unrelated to exercise; general weakness; history of taking cholesterol lower medications (i.e. statins):
Muscle inflammation or muscle aches from cholesterol medication (myositis or myalgia), Bakers cysts, vein problems, either venous thrombosis or venous insufficiency.
Non painful repetitive leg moment that impede sleep:
Restless leg syndrome (Periodic limb movement disorder)
Numbness, tingling, and “electric” pain, with secondary cramps unrelated to sleep or exercise.
Peripheral neuropathy (nerve disorder caused by diabetes, poor circulation, and sometimes, unknown causes)
Cramps accompanied by metabolic signs or symptoms:
Kidney failure, Dialysis.
Cramps accompanied by jaundice, weight loss, weakness, or signs of alcohol misuse:
Cirrhosis of the liver.
(chart adapted from Best Practice Advocacy Centre New Zealand)
Alaska Vein Clinic • 3300 Providence Drive, Suite 309 • Anchorage AK • 99508
Tel 907-222-6240 • Fax: 907-222-6870