MAO-B Inhibitors

Key Facts

  • MAO-B inhibitors are use by themselves for modest symptom control in early PD or in combination with other medications.

Brain monoamine oxidase (MAO) converts dopamine into inactive substance. By blocking MAO, more dopamine is available. MAO–B inhibitors don’t have the same side effects as MAO-A inhibitors, and therefore side effects associated with elevated concentrations of adrenaline-like substances –as, for example, hypertension-are avoided.

Since MAO-B inhibitors do provide modest benefit for the motor features of PD, they are usually used as early monotherapy or as an adjunct (add-on) to other medications, including levodopa. When used in combination with other medications, MAO-B inhibitors may reduce “off” time and extend “on” time.

Presentation

Dosages in Milligrams

Typical Treatment Regimens

Indications for Usage

Selegiline

(l-deprenyl, Eldepryl®)

5

5 mg twice a day

Monotherapy for slowness, stiffness, and tremor; adjunct therapy for motor fluctuations

Rasagiline (Azilect®)

0.5, 1.0

1 mg once daily

Same as above

Zydis selegiline HCL

Oral disintegrating

(ZELAPAR®)

1.25, 2.5

1.25-2.5 mg once daily

Same as above

 

Prescription Recommendations

Rasagiline

  • Prescribe: Rasagiline 0.5 mg, 1 mg
  • Instruct: Either 0.5 mg daily or 1 mg daily
  • Most common is 1mg a day
  • Usually there is no interaction with cheese or wine as it is a low dose MAO-B
  • If pharmacies warn you not to mix with antidepressants be aware that most movement disorders neurologists routinely mix and just monitor
  • Note that interaction with new antidepresants and rasagiline are rare. Monitor patients for Serotonin syndrome (flushing, hypertension, agitation)
  • Avoid meperidine in a patient taking rasagiline

Selegiline

  • Prescribe: Selegiline 5 mg (tablet or capsule) or disintegrating tablet 1.25 mg
  • Instruct: Either 5 mg or 10 mg daily (tablet or capsule) or 1-2 disintegrating tablets each morning
  • Usually selegiline is given 5 mg in the morning and 5 mg at noon (metabolites may affect sleep if given later in the day)
  • Usually there is no interaction with cheese or wine as it is a low dose MAO-B
  • If pharmacies warn you not to mix with antidepressants be aware that most movement disorders neurologists routinely mix and just monitor
  • Note that interaction with new antidepresants and selegiline are rare. Monitor patients for Serotonin syndrome (flushing, hypertension, agitation)
  • Avoid meperidine in a patient taking selegiline

Side Effects

  • Nausea
  • Dry mouth
  • Lightheadedness
  • Constipation
  • Agitation
  • Insomnia: common with selegiline (take only in the morning), keep medication dose as low as possible
  • Vivid dreams and hallucinations
  • Standard oral selegiline is converted to an amphetamine-like by-product which may contribute to side effects of jitteriness and confusion

Note: Taking MAO-B inhibitors with the heavy consumption of aged cheeses or wines high in tyramine may raise blood pressure to dangerous levels.

 

References: 

Ahlskog JE. Parkinson’s Disease Treatment Guide for Physicians. New York, NY: Oxford University Press; 2009.

Ahlskog JE. The Parkinson’s Disease Treatment Book: Partnering with Your Doctor to Get the Most from Your Medications. New York, NY: Oxford University Press; 2005.