Selegiline is a prescription medication that helps reduce symptoms of early-stage Parkinson\u2019s disease and is also effective against depression. It is also sometimes used \u201coff-label\u201d to treat some symptoms of ADHD, and some early research suggests it may have a number of other interesting effects. Read on to learn more about the common uses of this drug and how it works!<\/p>\n
<\/p>\n
Disclaimer:<\/em><\/strong> This post is <\/em>not<\/em><\/strong> a recommendation or endorsement for selegiline. This medication is only approved for the treatment of certain specific medical conditions, and can only be taken by prescription and with oversight from a licensed medical professional. We have written this post for informational purposes only, and our goal is solely to inform people about the science behind selegiline\u2019s effects, mechanisms, and current medical uses.<\/em><\/p>\n Selegiline – also known as L-deprenyl<\/em> – is a drug similar in structure to the neurotransmitter phenylethylamine<\/em> [R<\/a>].<\/p>\n It has a wide spectrum of uses, the most common being ones that involve brain health.<\/p>\n Officially, it has been FDA-approved for the treatment of Parkinson\u2019s disease and depression. Selegiline is also sometimes used \u201coff-label\u201d to treat ADHD.<\/p>\n Selegiline primarily blocks the activity of MAO-B<\/a> and – at higher doses – also MAO-A<\/a>. These enzymes break down dopamine<\/a> and other monoamine neurotransmitters (serotonin<\/a> and noradrenaline<\/a>). Thus, by blocking the activity of these enzymes, selegiline increases the overall level of these neurotransmitters [R<\/a>].<\/p>\n Some evidence also suggests that selegiline can be metabolized into by-products that may further increase dopamine levels in the brain, such as [R<\/a>, R<\/a>]:<\/p>\n While many different specific mechanisms may be involved in its effects, overall it is believed that selegiline\u2019s effects come primarily from higher levels of dopamine, serotonin, and noradrenaline throughout the brain.<\/p>\n Selegiline has a number of primary medical uses that have been fully approved by the FDA. Although this means that the evidence for its efficacy in these conditions is very strong, always keep in mind that this is a prescription medication that must only<\/strong> be used under the direction and supervision of a qualified medical professional.<\/p>\n One of the primary and most common uses for selegiline is to treat the symptoms and progression of Parkinson\u2019s disease (PD).<\/p>\n This use stems primarily from selegiline\u2019s ability to increase dopamine levels in the brain. This is important because many of the symptoms of Parkinson\u2019s are caused by reduced levels of dopamine as cell death spreads throughout dopamine-related parts of the brain [R<\/a>, R<\/a>].<\/p>\n Relatedly, it is believed that increased dopamine levels may compensate for the loss of dopamine neurons in PD, which may be why dopamine-enhancing drugs such as selegiline have been reported to improve the movement impairments characteristic of Parkinson\u2019s disease (especially slowness of movement, or bradykinesia<\/em>) [R<\/a>, R<\/a>].<\/p>\n For example, selegiline was reported to improve motor symptoms in 292 patients with early Parkinson\u2019s disease (double-blind randomized controlled trial) [R<\/a>].<\/p>\n Similarly, in a double-blind randomized controlled trial of 157 Parkinson\u2019s disease patients, selegiline (10 mg\/day) delayed the need for levodopa<\/a> therapy. It was also reported to slow down the progression of Parkinson\u2019s disease symptoms when used in combination with levodopa, compared to just levodopa alone [R<\/a>, R<\/a>, R<\/a>].<\/p>\n In addition to increasing dopamine levels, some evidence suggests that selegiline may also block the effects of MPTP, a neurotoxic compound that causes permanent symptoms of Parkinson\u2019s [R<\/a>].<\/p>\n Unfortunately, while several of the above studies have reported that selegiline may slow down the progression of symptoms in Parkinson\u2019s disease, it may not ultimately increase lifespan in PD patients.<\/strong> For example, one study found that while selegiline delayed the motor impairments of Parkinson\u2019s patients, this effect did not translate into reduced mortality rates [R<\/a>].<\/p>\n Another common medical use of selegiline is to treat depression.<\/p>\n It is generally believed that selegiline acts as an antidepressant due to its reported ability to increase the levels of dopamine, serotonin, and norepinephrine<\/a> throughout the brain [R<\/a>].<\/p>\n A meta-analysis of 5 different clinical studies reported that selegiline helped alleviate several key symptoms of major depression, including [R<\/a>]:<\/p>\n Another meta-analysis of 5 short-term trials (with a combined total of 352 subjects) concluded that selegiline significantly improved several different symptoms of major depressive disorder [R<\/a>].<\/p>\n According to one double-blind randomized controlled trial of 322 subjects with major depression<\/a>, depressed patients who received selegiline were significantly less likely to relapse, or took a longer time to relapse [R<\/a>].<\/p>\n Selegiline has also been reported to improve symptoms of apathy in 4 patients following severe brain injury [R<\/a>]. Because apathy is also one of the main symptoms of depression, this could be considered additional evidence for its effectiveness in alleviating depression.<\/p>\n However, not all of the available evidence supports the efficacy of selegiline in depression.<\/strong> For example, in one double-blind randomized controlled trial in 308 adolescents (12-17 years old) with major depressive disorder, selegiline was reported to have the same effect as an inactive placebo treatment [R<\/a>].<\/p>\n Nonetheless, while not all of the evidence out there unanimously supports selegiline\u2019s effectiveness as an antidepressant, the fact that it has been officially approved by the FDA for the treatment of depression indicates that the overall weight of the evidence is considered by medical experts to be quite strong.<\/p>\n Occasionally, doctors will prescribe medications to help treat conditions that fall outside of the official uses approved by the FDA – also known as \u201coff-label<\/em>\u201d drug use [R<\/a>]. Usually this is done because there is actually decent evidence that the drug may help, although this evidence might not be quite strong enough to get full FDA approval (which generally has very strict requirements).<\/p>\n As always, however, always remember that the decision to use medications in this way can only be made by a licensed medical professional.<\/p>\n Although selegiline has not been officially FDA-approved for this purpose, it is not uncommon for doctors to prescribe this medication in order to help improve or control the symptoms of ADHD.<\/p>\n The main rationale for using selegiline in this way stems from its potential to increase dopamine levels throughout the brain. One of dopamine\u2019s many important functions is to promote attention and focus<\/a>. Additionally, low levels of dopamine in certain specific parts of the brain are believed to be responsible for some of the attention problems frequently seen in ADHD [R<\/a>].<\/p>\n Although the evidence for this use of selegiline is not quite as strong as it is for Parkinson\u2019s and depression, there is still considerable scientific support behind its use in ADHD. For example, in a double-blind randomized controlled trial in 11 children with ADHD, selegiline was reported to improve sustained attention, learning, and peer interactions, while also reducing hyperactivity [R<\/a>].<\/p>\n Similarly, in different two double-blind randomized controlled trials with 40 and 28 children each, this drug was reported to be as effective as methylphenidate<\/em> (a central nervous system stimulant, commonly sold as Ritalin) in improving the symptoms of ADHD. Better yet, selegiline was also reported to cause fewer side effects [R<\/a>, R<\/a>].<\/p>\n However, at least one study contradicts some of this evidence: in one study of 24 adults with ADHD, selegiline was reported to be no more effective than placebo in improving ADHD symptoms [R<\/a>].<\/p>\nWhat Is Selegiline?<\/strong><\/span><\/h2>\n
Mechanism of Action<\/strong><\/span><\/h3>\n
\n
Official Medical Uses<\/span><\/h2>\n
1) Selegiline and Parkinson\u2019s Disease<\/span><\/h3>\n
2) Selegiline and Depression<\/strong><\/span><\/h3>\n
\n
Off-Label Uses of Selegiline<\/span><\/h2>\n
Selegiline and ADHD<\/span><\/h3>\n