Augmentation is a common and serious side effect of certain drugs taken for restless legs syndrome (RLS). It occurs in many people who take dopamine agonists or levodopa/carbidopa. Other treatments for RLS are less likely to cause augmentation.1,2
What are the signs of augmentation?
Augmentation is when RLS symptoms get worse instead of better even when the dose of medicine is increased. Signs of augmentation include:1-3
- An increase in the intensity of RLS symptoms
- Symptoms start earlier in the day
- Symptoms spread to other areas of the body, such as the arms, face, or trunk
- Symptoms begin more quickly during periods of rest than before
- The current dose no longer works to control symptoms or works for shorter periods of time
- Higher doses do not control symptoms any longer
These symptoms may be worse than the original RLS symptoms before drug treatment.
How quickly does augmentation begin?
Between 50 and 70 percent of people who take these drugs eventually experience augmentation within 10 years. It can begin as soon as 6 months after treatment begins.3,4
What causes augmentation?
Doctors do not know what causes augmentation. Doctors do know that low iron levels in the body increase the chances of developing augmentation. Some studies suggest that people with RLS need higher than normal levels of iron.
How is augmentation diagnosed?
To be diagnosed with augmentation, you must have been taking a drug that increases the levels of dopamine in the body. There is no one test to diagnose augmentation. Your doctor will begin by ruling out other conditions that can mimic or worsen augmentation. These include:2
- Low iron levels
- Drugs side effects from some antidepressants, antihistamines, cold remedies, sleep aids, and anti-nausea drugs
- Lack of exercise
- Other sleep disorders
- Triggers such as caffeine, alcohol, or nicotine
- Advanced age
Other lifestyle issues that can make RLS symptoms worse include lack of sleep, shift work, and other sleep disorders such as sleep apnea or insomnia.2
How is augmentation treated?
There are several options to treat augmentation. Your doctor may switch you to an alpha-2-ligand or low-dose opioid, 2 other drugs that can help with RLS symptoms. Augmentation may be difficult to diagnose. Your doctor may need to adjust your medicine.2
Another option may be to split your dose of dopamine agonist into 2, with 1 dose taken in the early evening and 1 dose taken before bedtime.1
Things to know about augmentation
Your doctor may avoid prescribing dopamine agonists for you due to the potential for augmentation. That is why alpha-2-ligands such as Horizant, Lyrica, or Neurontin are generally the first choice to treat people who need daily treatment for their RLS. Dopamine agonists have been used to treat RLS. But they are less popular due to the potential for augmentation and the development of newer drugs.2
Levopoda was the first drug known to help treat RLS but is generally avoided now because augmentation began in 60 percent of people after just 2 months.1
If you feel signs of augmentation, do not stop taking your RLS drugs suddenly. Talk with your doctor first.
Before beginning treatment for RLS, tell your doctor about all your health conditions and any other drugs, vitamins, or supplements you are taking. This includes over-the-counter drugs.