Restless Legs and Alcohol

Alcohol is the general common name given to ethanol or ethyl alcohol. This volatile, flammable, colorless liquid is a psychoactive drink and an ancient recreational drug to man.

Alcohol is made from the fermentation of sugar. Beyond its use in alcoholic beverages, it also serves as solvent and fuel.

When alcohol mixes with water, it releases energy and reduces the total volume of the combination. This is the reason that alcoholic drinks with high ethanol content produce a burning sensation on tissues and mucosal membranes.

Alcohol can cause intoxication and although this promotes drowsiness and sleep, the quality of such sleep is affected by other effects of alcohol.

This sleep disturbance can worsen the symptoms of restless leg syndrome. Because of this, the general advice is that alcohol should be avoided by people living with the neurological syndrome.

Effects of Alcohol on the Body

Alcohol has a net depressant effect on the central nervous system. However, it affects many systems and pathways in the brain often producing complex and contrasting interactions.

Alcohol has significant effects on the levels of neurotransmitters in the brain. It binds to serotonin, GABA, and acetylcholine receptors and also increases the level of dopamine in the brain.

While low doses of alcohol increase sleeping time and can even promote deep sleep, these effects are lost with the consumption of moderate to high doses. Alcohol is more likely to cause sleep disturbance amongst experienced drinkers rather than occasional drinkers.

By causing sleep deprivation, alcohol will also cause fatigue and restlessness.

The spectrum of alcohol effects ranges from euphoria and lethargy in small doses to confusion, stupor, and coma in high doses.

Even in moderate doses, alcohol reduces efficiency in the areas of the brain concerned with planning, coordination, and movement. It also causes hyperactivity both in speech and movement.

Also, alcohol consumption reduces the production of antidiuretic hormone. This hormone is responsible for the reabsorption of water in the kidney tubules. By blocking this hormone, alcohol increases diuresis and can cause dehydration.

The increased diuresis translates to excessive urination which itself can disturb the quality of sleep.

In excessive doses, alcohol fully becomes a depressant in the central nervous system. It activates the GABA (gamma-aminobutyric acid) system in the brain and causes memory impairment.

Alcohol intoxication also causes ataxia. Ataxia refers to the uncoordinated movement of parts of the body. It can affect the limbs and contribute to the irresistible urges of restless leg syndrome.

The addictive potential of alcohol is well studied. Even though some people develop tolerance to high doses of alcohol, chronic consumption, and alcoholism still damages different organs of the body including the kidneys and the brain.

Alcohol withdrawal can also produce serious side effects. Sleep disruption, hyperactivity, seizures, delirium, and hallucinations are some of the symptoms experienced by chronic alcoholics while abstaining from alcohol.

While these effects soon diminish and disappear, they can worsen the symptoms of restless leg syndrome for the few days during which they are at their peak.

Alcohol and Restless Leg Syndrome

A 2006 study published in the journal, Alcoholism: Clinical and Experimental Research detailed the effect of moderate alcohol consumption on periodic leg movement.

The researchers took 20 leg movements per hour of sleep to be significant.

The results showed that alcohol consumption was more likely to cause restless legs in women than men. There was significant leg movement in 3 times more women who took 2 or more alcoholic drinks per day than those who do not.

In men, the population of those who drank the same quantity of alcohol daily and experienced restless legs was double those who did not drink and still experience periodic leg movement.

The researchers concluded that alcohol consumption had significant effects on the symptoms of restless leg syndrome in susceptible individuals.

The main reason for the restless leg movements was believed to be alcohol-induced sleep disturbance.

Different studies have established that the two neurotransmitters most affected by alcohol are dopamine and GABA.

Alcohol increases dopamine levels by inhibiting the enzymes that break down the neurotransmitter. Although alcohol increases the level of dopamine in the brain, such increases occur in different parts of the brain.

While increasing dopamine levels in the substantia nigra is the target of medications used for treating restless leg syndrome, outside of the midbrain dopamine is just another excitatory neurotransmitter that can cause restlessness and hyperactivity.

Dopamine is not the only neurotransmitter increased by alcohol. Serotonin levels are also increased and both neurotransmitters affect the reward system of the brain.

Chronic alcohol consumption can damage neurons and disrupt this system enough to cause alcohol addiction.

The effect of alcohol on GABA receptors leads to inhibition of brain activities which may lead to memory loss. The alcohol-GABA interaction does not affect the cause or outcome of restless leg syndrome in any significant way.

Alcohol Consumption and Sleep Disruption

The major way by which alcohol worsens the symptoms of restless leg syndrome is through sleep disruption.

Initially, moderate alcohol consumption may cause drowsiness and increase the onset of sleep but when the alcohol is metabolized in the body, it disrupts sleep by interfering with the progression of the different stages of sleep.

Alcohol suppresses REM (rapid eye movement) and Stage 1 sleep in the first half of a night’s sleep while recreating those stages of sleep in the second half where they should not be.

Instead, in the first half of sleep, slow-wave sleep (SWS) or non-REM is increased.

This reversal of sleep architecture causes restlessness in the second half of sleep when the body should be most at rest. Some people do develop tolerance to moderate alcohol doses so that their sleep architecture adjusts to the effect of alcohol but high doses and chronic alcoholism reduce both the length of sleep and the rest derived from it.

Secondary alcohol effects such as increased urination and fatigue also disrupt sleep and increase periodic leg movement.

Sleep disruption is also a common symptom of alcohol withdrawal. This is caused by reduced melatonin production which prolongs the onset of sleep.

Furthermore, increased secretion of cortisol makes it difficult to maintain sleep because the hormone promotes carbohydrate metabolism and supplies excess energy that may present as restlessness during sleep.