Insomnia is difficulty getting enough sleep or trouble sleeping without interruption. You may have difficulty falling asleep, may wake up too early, or may wake up periodically during the night. Insomnia of any kind can keep you from feeling rested and refreshed during the day.
Almost all of us have episodes of insomnia at some time, but insomnia is not a short-term problem for everyone. Insomnia is classified as chronic when it happens almost every night for at least one month. Insomnia can be related to a medical or psychiatric illness, can be caused by mental stress or excitement, or can be caused by your daytime and bedtime habits.
Your habits and surroundings are the usual causes of short-term insomnia problems. Factors that contribute to insomnia can include:
Stress or anxiety
A change in sleeping environment (being a guest at a hotel or a relative's home)
An uncomfortable sleeping environment (too hot, too cold, too bright, too noisy)
An uncomfortable mattress
Pajamas that are too tight
Having a bed partner who snores or has disruptive sleep patterns
Watching television, reading a book or problem-solving in your bed, so your brain associates lying down in bed without activities other than sleeping
Eating a heavy meal before bedtime
Taking a prescription medication that has insomnia as a side effect
Drinking alcoholic beverages before bedtime
Having a high intake of beverages containing caffeine (coffee, tea, cola) during the day
Exercising immediately before bedtime
Not exercising enough during the day, so you have energy to spare
Taking a hot bath or shower before bed
Traveling to a different time zone
Traveling to a much higher altitude
Pregnant women are particularly vulnerable to insomnia. Women who are pregnant may have insomnia because of hormone changes, heartburn, leg cramps or a need to urinate more frequently. In addition, the unborn baby's increasing size often makes it harder for the mother to find a comfortable sleeping position.
Chronic insomnia may be caused by a medical or psychiatric problem. Some common causes of chronic insomnia include:
Psychiatric illness, especially depression or post-traumatic stress disorder (PTSD)
Chronic medical illnesses, especially kidney disease, heart failure or asthma
Painful illnesses, especially arthritis, neuropathy, acid reflux or cancer
Hormone imbalance, especially menopause or hyperthyroidism
Taking a prescription medicine that has insomnia as a side effect
Restless legs syndrome -- This disorder causes uncomfortable sensations in the legs. Symptoms can include twitching of the legs, a habit of repetitive leg movements, and leg cramps
Obstructive sleep apnea
Sleep apnea is a common condition. However, often the people that have this problem don't realize it. Snorers or people who are overweight may have repeated episodes in which breathing stops for 10 seconds to 30 seconds during sleep, just when the person is relaxing into deep sleep.
Sleep apnea is caused most often by relaxing the tongue and throat tissues, which can settle into a position that closes your airway. Your body reacts to sleep apnea by releasing adrenaline-like "alarm" hormones so you will awaken and resume breathing. These hormones keep you awake for periods of the night.