What is a suitable initial medication to control symptoms of Parkinson's disease (PD) in a patient not currently on any medication?

From the Guidelines

Levodopa/carbidopa is the most suitable initial medication to control symptoms of Parkinson's disease (PD) in a patient not currently on any medication, due to its efficacy in replenishing dopamine in the brain and addressing the fundamental neurotransmitter deficiency in PD 1. When initiating levodopa/carbidopa, a common starting regimen is 25/100 mg (carbidopa/levodopa) three times daily with meals, which can be gradually increased as needed. Some key points to consider when starting levodopa/carbidopa include:

• Monitoring for side effects such as nausea, vomiting, abdominal pain, dyspepsia, constipation, weight decrease, dry mouth, diarrhea, anorexia, and GI disorders 1
• Potential for impaired nutritional status and risk for malnutrition, particularly with increasing doses of levodopa 1
• Association with hyperhomocysteinemia, which may require supplementation with vitamins B6, B12, and folate 1
• Potential for motor fluctuations and dyskinesias with long-term use 1 Alternatively, for younger patients (under 65) or those concerned about levodopa-induced dyskinesias, dopamine agonists like pramipexole or ropinirole may be considered as initial therapy 1. MAO-B inhibitors such as rasagiline represent another option for patients with milder symptoms 1. The choice of initial medication depends on the patient's age, symptom severity, and comorbidities, and should be individualized to optimize symptom control and minimize side effects 1.

From the FDA Drug Label

The effectiveness of rasagiline tablets for the treatment of Parkinson’s disease was established in four 18-to 26-week, randomized, placebo-controlled trials, as initial monotherapy or adjunct therapy. Study 1 was a double-blind, randomized, fixed- dose parallel group, 26-week study in early Parkinson’s disease patients not receiving any concomitant dopaminergic therapy at the start of the study. Rasagiline tablets (1 or 2 mg once daily) were superior to placebo on the primary measure of effectiveness in patients receiving six months of treatment and not on dopaminergic therapy.

• Rasagiline is a suitable initial medication to control symptoms of Parkinson's disease (PD) in a patient not currently on any medication, as shown in Study 1 where rasagiline tablets 1 mg/day and 2 mg/day were superior to placebo in patients with early Parkinson's disease not receiving any concomitant dopaminergic therapy 2.
• The recommended initial dose is 1 mg/day or 2 mg/day, as both doses were effective and comparable in Study 1.

From the Research

Suitable Initial Medication for Parkinson's Disease

• Dopamine agonists (DA) are often used as first-line monotherapy for the symptomatic control of Parkinson's disease (PD) 3.
• Dopamine-based therapies, such as carbidopa-levodopa and dopamine agonists, typically help initial motor symptoms 4.
• Rasagiline, a monoamine oxidase-B (MAO-B) inhibitor, has been shown to be effective in monotherapy and in combination with other antiparkinsonian therapies, and may be considered as an initial medication for PD patients 5, 6.
• The choice of initial medication may depend on the individual patient's symptoms, disease stage, and other factors, and should be determined by a healthcare professional.

Considerations for Initial Medication

• Rasagiline has been demonstrated to improve motor and some non-motor symptoms in both early and advanced PD patients, and exhibits neuroprotective and antiapoptotic properties 5.
• The combination of rasagiline with other dopaminergic drugs has been shown to be efficacious in improving motor fluctuations and dyskinesias 6.
• However, rasagiline may be associated with impulse control disorders, such as hypersexuality, in some patients 7.
• The potential benefits and risks of each medication should be carefully considered when selecting an initial medication for PD patients.