Medications for Rett syndrome typically address communication and movement issues. While they cannot cure the disorder, they can help manage the complications and symptoms of Rett syndrome including seizures and muscle spasms.
Many of the medications for Rett Syndrome were created for other conditions, but their benefits have been found to be helpful in treating children and adults with the disorder. Medications that have been used include:
- Naltrexone (Revia)
- Bromocriptine (Parlodel)
L-Dopa, a drug most commonly used to treat Parkinson's disease, is used in patients with late stage Rett syndrome for "improvement in rigidity which may accompany the stage of late motor deterioration" (Hagberg). It can improve stiffness in the muscles once the ability to walk has been lost. The drug does not seem to have any significant benefits for earlier stages of the disorder.
Naltrexone is a type of sedative that is typically used to counteract the opium-inducing effects of drugs in addicts. According to the International Rett Syndrome Foundation, "independent studies have shown that use of naltrexone in higher or lower doses may be beneficial in controlling irregular breathing and seizures, and in alleviating screaming spells." The reason naltrexone is thought to work in children with Rett syndrome is partly due to its sedative effects and partly, says the foundation, due to the fact that children with this disorder have an "unusually high level of naturally-occurring opium-like brain chemicals called endorphins in the spinal fluid."
One problem with using naltrexone is the impact its sedative effect may have on a child's development. If the dosage is too low, it may not be effective. If it is too high, the child may lack the alertness to learn and interact with his or her environment. Naltrexone is usually prescribed in the second and third stages of Rett syndrome, typically after one year of age.
Another medication used to treat the symptoms of Rett syndrome is bromocriptine. Also known as Parlodel, it is a "dopamine receptor agonist' (National Center for Biotechnology Information) and reduces the amount of prolactin in the body.
Drs. Zapella et al. found, in a 1990 study, that girls treated with bromocriptine for six months showed "improvements in communication and relaxation" and exhibited decreased hand movements. Unfortunately, the effects of the drug appeared to wear off after two months if treatment was not maintained, and effectiveness reduced over time if the girls stayed on the medication. Further studies are being conducted to determine the value of long term use of bromocriptine. This medication is typically prescribed to patients with milder symptoms, or to those in the earlier stages of Rett syndrome.
L-Carnitine comes from lysine, an amino acid. It has been found to improve alertness, concentration, energy and muscle density, but is one of the medications for Rett syndrome that is supported more by anecdotal evidence than scientific research. Parents report that their children feel better and enjoy life more while taking L-Carnitine, but studies have not been able to provide any conclusive evidence. A known positive side effect of the drug is loose stools, which can help to alleviate the chronic constipation that often accompanies Rett syndrome. L-Carnitine is one of the medications for Rett syndrome prescribed in all stages of the disorder.
Medications Currently Being Researched
- dextromethorphan (in clinical trials)
- folate therapy
- stem cell therapy
Each of these treatment options is in the very early stages of research and testing, but as more is discovered about the genetic causes of Rett Syndrome, more avenues for treatment are beginning to emerge.
Hagberg, Bengt and Anvret, Maria. Rett Syndrome: Clinical and Biological Aspects. Mac Keith Press, 1993.
International Rett Syndrome Foundation. What Drugs Have Been Tried? https://www.rettsyndrome.org/about-rett-syndrome/faq.html#021
National Institute for Biotechnology Information. Bromocriptine. https://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0000569/
Zapella, M et al. "Bromocriptine in the Rett Syndrome." Brain Development, 1990.