Cramps are painful and involuntary spasms of one or a group of skeletal muscles. They occur when the nerves that supply the muscle/s exhibit explosive hyperactivity. They may last from seconds to minutes and can be initiated by a strong contraction and stopped by stretching the muscle/s.

Muscle cramps may be the symptom of an acquired or inborn systemic disease such as those that are associated with advanced kidney or liver disease, diabetes mellitus, Parkinson’s disease, diseases of the central and peripheral nervous systems, hyper or hypothyroidism and hyperparathyroidism.

To some people, they are occupational hazards as in the case of writer or musician’s cramps where nerve damage occurs because of overuse of some muscles.

They could also be caused by intake of drugs such as salbutamol, terbutaline and phenothizides. They can also be exercise-associated. Traditionally, these latter form of cramps have been attributed to water or electrolyte (especially sodium) loss or to a very hot environment, but studies have shown that most athletes who cramp are not dehydrated and most cramps occur in conditions when the environment is neither too cold nor too hot.

Many experts now think that exercise-associated cramping is related more to muscle fatigue than anything else. Although the possibility that, in some cases, water and electrolyte imbalance can indeed precipitate or at least aggravate muscle cramping cannot be discounted.

Indeed, recurrent muscle cramps may herald the presence of a serious illness, but in most instances, they are just painful but otherwise harmless disorders that occur without any apparent cause in healthy individuals.

In fact, outside of exercise-associated cramps, the most common type of cramps is a benign condition called idiopathic leg cramps, the type of cramp that you apparently have. Idiopathic leg cramps occur at rest and usually at night, while asleep, when the normal muscle reflex is often exaggerated.

It involves the calf, thigh and small muscles of the foot and is more common among the elderly perhaps because muscles of older people tire more easily than those of young adults. About one third of people over 60 years and half of people over 80 years suffer from cramp at rest. Of these, 40 percent experience more than three episodes per week.

Idiopathic nocturnal leg cramps may persist for weeks to months but they usually do not lead to serious complications. During an acute attack, passive stretching and massage of the affected muscle is usually enough to relieve the spasm and pain.

How can one prevent idiopathic leg cramps? Preventive measures against leg cramps at night include both mechanical and pharmacological measures.

Many experts recommend muscle stretching exercises three times a day plus calf-muscle stretching with wall push-ups at night. Likewise, warm compress could be applied over the commonly-affected muscles for 10-20 minutes before going to bed. The efficacy of these measures has however not been clearly established yet.

If the leg cramps are frequent, pharmacological treatment may be instituted, but this has to be under the supervision of a physician.. The only drug that has been shown to be effective in the treatment and prevention of idiopathic nocturnal cramps is quinine sulfate, a drug which, strangely enough, is an anti-malarial.

The efficacy of quinine sulfate in preventing leg cramps has been supported in the majority of well-designed studies, but its use is controversial. The US Food and Drug Administration does not allow sale of quinine-based products for leg cramps over-the-counter because potentially fatal hypersensitivity reactions and thrombocytopenia (a kind of blood disorder) can occur with its use.

Other adverse effects of the drug include headache, nausea, disturbed vision, chest pain, asthma and ringing of ears. In pregnant women, they can also cause miscarriages and birth defects.

Address inquiries on health matters to Dr. Eduardo G. Gonzales, DLSU College of Medicine, Dasmariñas, Cavite 4114.