Why is selegiline/imidopyr not recommended?

Selegiline/midopid(Selegiline) is a selective monoamine oxidase B (MAO-B) inhibitor, mainly used for the adjuvant treatment of Parkinson's disease, and has also been tried for the management of depression in some countries. It inhibits dopamine metabolism and prolongs dopamine activity in the brain, thereby improving symptoms such as tremor, stiffness and bradykinesia. However, in recent years, clinical guidelines and expert opinions have generally emphasized that the use of selegiline should be more cautious or even avoided as much as possible. This is based on multiple considerations.

First, there is a significant risk of drug interactions with selegiline. Because it inhibits monoamine oxidase, if used in combination with foods containing high tyramine or certain antidepressants (such as SSRIs, tricyclic drugs), it may lead to serious adverse reactions such as hypertensive crisis or serotonin syndrome. This characteristic limits its wide clinical application and forces doctors to repeatedly weigh it when prescribing.

Secondly, the efficacy of selegiline is relatively limited during long-term use. Studies have shown that compared with conventional drugs such as levodopa, selegiline has a milder effect in improving motor symptoms, and as the disease progresses, it often cannot maintain the desired effect alone. This means that in most patients with Parkinson's disease, it is more like an early adjunct drug rather than a core treatment, which also affects its clinical status.

In addition, there are certain issues with the tolerance of selegiline. Some patients may experience side effects such as insomnia, anxiety, dizziness, and blood pressure fluctuations during use. Since the metabolites of this drug include amphetamine-like substances, some studies have suggested that it may be related to central arousal symptoms, thereby affecting patients' sleep quality and life comfort. In contrast, subsequently developed new MAO-B inhibitors such as rasagiline are considered to be better in terms of safety and tolerability, and therefore have gradually replaced selegiline in guideline recommendations.

Reference: https://www.drugs.com/mtm/selegiline.html