Preventing leg cramps

Photo / Dean Purcell

You are sleeping peacefully when a painful sensation suddenly pierces your leg, jolting you awake. For many this is an all too familiar scenario.

You have plenty of company - about 70 per cent of adults over 50 experience night time these cramps.

They are a sudden involuntary contraction of the calf muscles that can happen at night or at rest. This contraction can last from a few seconds to 10 minutes.

It can sometimes affect the soles of the feet as well. It seems to occur in many older people, as well as pregnant women.

No one really knows what causes leg cramps exactly, however, we do know that dehydration can contribute to this, as well as a poor diet that is low in potassium and magnesium.

We also know that diuretic drugs which deplete potassium, sodium and magnesium, increase the risk of leg cramps, as do statin drugs, Ventolin and nifedipine.

Other people who are more at risk of leg cramps are diabetics, those with Parkinson's disease, hypoglycaemia, anaemia, thyroid problems and hypoglycaemia (low blood sugar).

Quinine used to be used and prescribed for this by doctors. It has been effective and used since the 1940s for cramp.

However, doctors have been advised not to prescribe quinine anymore because it is thought the risks of using it far outweigh its benefits.

Local and international reports of nasty side effects of quinine use include: thrombocytopaenia (very low platelets - platelets help to clog up tears in tissues), fatal cardiac arrythmias, interactions with drugs, tinnitus (ringing in the ears), permanent hearing and visual disturbances and kidney failure. It is okay to stop using quinine suddenly.

Things you can do to help prevent leg cramps:

* Drink plenty of water - this prevents dehydration.

* Eat a healthy diet with plenty of fruit and vegetables to get magnesium and potassium.

* Magnesium supplements work and are safe in all situations including pregnancy. The best magnesium to use is magnesium citrate or lactate twice a day, because these forms of magnesium are the most easily absorbed.

* Calcium - there is conflicting evidence about whether it works.

* Multivitamins - they can help but are not advised during pregnancy.

* Vitamin E 300IU will help.

* B12 and B complex have been found to be helpful.

* Regularly stretching your calves does not work.

* Wearing support stockings doesn't work.

It is important to be careful if you get pain in one leg for the first time - this needs to be checked with your family doctor in case it could be a deep vein thrombosis (blood clot).

This is especially the case if you have been laid-up for a while in bed with an illness, or on a long air trip.

It is very important that this is checked.

- Dr Frances Pitsilis
drfrances.co.nz

Photo / Dean Purcell