Narcolepsy, restless leg syndrome, somnolence by drugs, and interference with driving

Narcolepsy is a disease that disables for driving

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Narcolepsy is characterized by appearing at daytime of sharp, unstoppable episodes of sleep, that are enhanced with emotional situations, and that may or may not report excessive daytime somnolence among the attacks of sleep.

It usually starts in adolescence or at the beginning of the adult age, and it persists all life long. It is estimated that 1 of every 2000 people suffer it.

  • Symptoms: The patient reports irresistible sleep, and can show muscle hypotonia crisis with risk of fall, remaining motionless but consciousness and without respiratory disorders.
    The momentary paralyses are usually associated with sharp emotional reactions, laughter, or exercise.
    At times, when falling asleep or immediately after awakening, the patient wants to move and he momentarily cannot do it. It can be associated with a significant feeling of terror. It can be associated with hypnagogic phenomena, such as hallucinations or visual or auditory illusions that look real, at the beginning of sleep and more frequently when awakening.
    Other symptoms, often associated, are automatic behavior, memory disorders, blurred vision and diplopia.
    The sleep crises range from a few to many a day, and can last minutes or hours. They can awaken the patient from the narcoleptic sleep with the same facility as in a normal sleep, but can he can sleep again in a few minutes.
    The crises can appear under conditions of monotony leading to normal sleep, but also during moments of danger, for example while driving.
    At night the sleep episodes can be unsatisfactory and be interrupted by terrible nightmares.
    It has been associated with a higher risk of traffic accident and the drivers with this disorder show worse results in laboratory tests related to attention and alertness.
  • Treatment: It is individualized depending on the symptoms, psychological involvement, work and timetables, compliance with sleep hygienic measures, and the possibility for establishing small naps.
    Many patients require CNS stimulating drugs, that can be useful such as ephedrine, amphetamine, dextroamphetamine, centramine, and methylphenidate, divided into doses. The recommended doses are well tolerated and have no significant adverse events.
    Tricyclic antidepressants such as imipramine are recommended in the treatment of cataplexia.
    The combination of imipramine with stimulants can cause HT, so these patients should be carefully warned and monitored.


  • Narcolepsy is a disease that disables for driving due to the sudden uncontrollable crises of sleep, that occur in 60-80% of the patients while driving.
  • In those cases where the treatment controls unstoppable sleep and the associated disorders, the patient can drive, but always with a medical report indicating it.

The “restless leg” syndrome

This condition is one of the most frequent causes of insomnia and has a substantial impact on the quality of life of people who suffer it.

To date, it is a poorly known neurological disease and it continues to be treated as a rare disease even though between 5 and 10% of the Spanish population, some three million people, suffer it.

Its prevalence, that increases with age, is estimated to reach 27% of the population in 2010, particularly in the population over 45 years of age and in women.

It is characterized by an urgent , uncontrollable need to move the legs and the severe sensation of inconvenience and pain in the legs.

It is commonly associated with the appearance of varicose veins, edema, and skin ulcers, so the symptoms are attributed to problems such as rheumatic diseases or circulatory disorders.

Only in a small number of cases a proper diagnosis is made, even though this disease is quite common and can be diagnosed easily.

Most of the patients focus their comments in the impossibility to sleep, and cannot describe the inconveniences they suffer in the extremities. They do not really associate these symptoms with the disability for resting.

The patient with mild to moderate pain usually sleeps less than five hours at night, and that with chronic pain rests much less that other patients with sleep disturbances.

Furthermore, the lack of sleep and the poor quality of this, has an impact on the capacity to concentrate at daytime, leading to depression or poor mood, and causing daytime somnolence, that affects concentration when driving.

Furthermore, the restless legs syndrome also has a harmful impact on the activities that require immobility, and 60% of the patients find it difficult to seat or even to relax.

This means a social problem, since there are multiple activities such as traveling in car, that require a static or seated position.

The causes that can lead to the side effect of restless leg syndrome include anemia, renal failure, rheumatoid arthritis, and some drugs such as antidepressants or sedative antihistamines.

The treatment in mild cases is based on a healthy diet, avoiding sleep deprivation and the triggering factors, practicing exercise and postural measures, together with the application of bandages and measures of compression.

If this is not sufficient to solve the inconveniences, drug therapy will be used.

Advice on “restless legs” syndrome

  • A greater degree of recognition and information on the restless leg syndrome is necessary, including the very negative consequences of this disease on sleep, quality of life of those suffering it, and the increased risk when driving.
  • Drivers with restless legs syndrome with daytime somnolence should be advised against driving as long as the therapeutic measures used cannot control the clinical condition.
  • The recovery of an adequate night rest will allow the driver for driving again with the necessary concentration for his safety and that of others.

Somnolence due to drugs

Daytime somnolence is a frequent, little studied symptom, that causes 20% of traffic accidents and 50% of those that are fatal, for the reduced concentration while driving.

The most favorable time for somnolence is between 1 and 6 hours in the early morning and between 3 and 4 hours in the afternoon.

Sedative agents such as benzodiazepines, barbiturates and antihistamines are those causing more somnolence, but there are many other that affect night rest leading to secondary daytime somnolence.

Among the drugs that cause insomnia and daytime somnolence there is a long list including, amongst others, amphetamines, MAOI, beta-blockers, methylxanthines, corticoids, some antibiotics and antivirals, thyroid hormone and tricyclics.

Advice on somnolence due to drugs

  • The physicians should warn about the possibility of disorders in the sleep rhythm, virtually with all drugs.
  • Sometimes the somnolence caused by certain drugs only occurs in the first days of treatment, so we should warn the patients not to drive if this occurs until they have adapted to the new situation in long-term therapies.
  • The patient should know that, if this happens to him, he must tell his physician in order to establish changes in the treatment regimen, either in the drug or the schedule, and prevent the somnolence when driving, with the risk of accident.