Twitches and jerks of the muscles, or myoclonus, can be distressing and uncomfortable. Myoclonus is described as a sudden, involuntary contraction of a muscle or a group of muscles, the National Institute of Neurological Disorders and Stroke says. These jerks and twitches are not under voluntary control.
Sleep Myoclonus
Sleep myoclonus is a sudden and sometimes distressing muscle jerk that happens just as a person is falling asleep, according to the NINDS. Most of those with sleep myoclonus are not overly troubled by it, and do not require treatment. Sleep myoclonus, also known as sleep starts or hypnic jerks, are very common. The cause of these muscle jerks is unknown, but sleep deprivation increases the risk, according to medical commentator Dr. Andrew Weil. Taking steps to improve sleep may alleviate sleep myoclonus.
Medications
Certain medications can cause a side effect of muscle twitches and jerks. Opioid, or narcotic, pain relievers taken for an extended period of time can cause myoclonic jerks, the National Cancer Institute explains. Switching to another opioid pain reliever may resolve the problem. In cases where the sufferer is very near death, medication to control the myoclonic jerking will commonly be given instead of changing the medication. Selective serotonin reuptake inhibitors, or SSRIs, can also have a side effect of myoclonic twitches and jerks, according to MedlinePlus, a publication of the National Institutes of Health. SSRIs are a category of antidepressants that includes Paxil, Prozac, Zoloft and Celexa.
Tourette's Syndrome
Tourette's syndrome is a neurological disorder, the NINDS explains. It is characterized by tics, or rapid and involuntary movements. Excessive blinking, grimacing, shoulder shrugging and muscle jerks of the head and shoulders are examples of common simple tics. Complex tics, such as sniffing or touching objects, may seem to be purposeful, but are not under voluntary control. Other complex tics include sudden outbursts of swearing or repeating the words of others. The first symptoms of Tourette's syndrome are often a jerking of the head and shoulders that starts in early childhood. The cause is unknown, although research suggests abnormalities in brain chemicals or in certain parts of the brain.
Parkinson's Disease
Parkinson's disease is a progressive disorder of the neurological system that affects movement, according to the MayoClinic.com. Sufferers may experience tremors in the hands, a reduction or lack of facial expression, slowed and monotone speech, loss of balance, difficulty chewing and swallowing, stooped posture and a shuffling walk. Eventually, disorders of memory and other mental functions can occur. The cause is unknown, although genetics, possibly combined with environmental factors, are believed to play a role.
