Which medication is added in the treatment of Parkinson's and inhibits MAO B mechanisms?

Selegiline is a medication specifically designed to inhibit the enzyme monoamine oxidase B (MAO B), which plays a critical role in the metabolism of dopamine in the brain. By inhibiting this enzyme, selegiline increases the levels of dopamine and prolongs its effects, which can be particularly beneficial in managing the symptoms of Parkinson's disease. Parkinson's is characterized by the degeneration of dopaminergic neurons, leading to reduced dopamine levels. Therefore, using selegiline not only helps enhance dopamine availability but can also be used as an adjunct to other Parkinson's treatments, such as levodopa, to improve overall efficacy and control of symptoms.

In contrast, other medications listed do not specifically target MAO B. Tranylcypromine and phenelzine are non-selective MAO inhibitors that affect both MAO A and MAO B, but they are primarily utilized in treating depression rather than Parkinson's disease. Lithium is an entirely different class of medication used mainly as a mood stabilizer for bipolar disorder and does not play a role in the treatment of Parkinson's. Thus, selegiline stands out as the appropriate choice for its specific action in the context of Parkinson's treatment.