The information provided here is meant to give you a general idea about each of the medications listed below. Only the most general side effects are included, so ask your doctor if you need to take any special precautions. Use each of these medications only as recommended by your doctor and according to the instructions provided. If you have further questions about usage or side effects, contact your doctor.

Medications for Parkinson’s disease work in a variety of different ways. The primary strategy is to increase the amount of dopamine or to activate the dopamine receptor, as it is the neurotransmitter pathway that is decreased in people with Parkinson’s disease. Although most people respond to medications initially, the effects may wear off over time as the disease progresses. When a particular medication stops working, your doctor may have to increase the dose, switch medications, stop and then restart a medication, or add on another medication. In addition, many people experience disabling side effects (specifically, rapid “wearing-off” of the drug and abnormal movements, called dyskinesias) from long-term dopamine-replacement therapy, which requires a decrease in dose and possible substitution of another medication or other form of therapy.

Prescription Medications

Levodopa

Levodopa is the most effective treatment for symptoms. It is a precursor to dopamine and converted to dopamine once transported into the brain.

Common names include:

    
  • Dopar
  • Larodopa
  • Levodopa and Carbidopa

    Common names include:

        
  • Carbidopa/levodopa
  • Carbidopa/levodopa controlled-release
  • Carbidopa/levodopa/entacapone
  • Levodopa helps increase the amount of dopamine within the brain. This can help improve symptoms of Parkinson’s disease, particularly rigidity and slowness. Unfortunately, the body metabolizes (breaks down) this drug very quickly, so you’ll have to take another dose fairly often. As a result, you’ll often be given a medication that combines levodopa with carbidopa, a substance that slows the breakdown of levodopa. You’ll only have to take this medication every 4-6 hours.

    If you’re taking levodopa alone, don’t take vitamin B6 supplements without your doctor’s knowledge since they can speed up the breakdown of levodopa. Because bananas, egg yolks, lima beans, meats, peanuts, and whole grain cereals all contain large amounts of vitamin B6, ask your doctor how much of these food items you should eat on a daily basis.

    Some people notice less effect from levodopa and levodopa/carbidopa combinations over time. The drugs may seem less effective, or their benefits may stop even before it’s time for the next dose. If this happens, talk to your doctor about increasing the dosage or increasing how frequently you take the medication.

    Don’t ever suddenly discontinue using these medications, unless your doctor advises it.

    Possible side effects include:

        
  • Nausea
  • Vomiting
  • Lightheadedness
  • Dry mouth
  • Nightmares
  • Nervousness
  • Anxiety
  • Decreased appetite
  • Increased intestinal gas
  • Low blood pressure
  • Palpitations
  • Confusion
  • Agitation
  • Psychosis, paranoia, mania
  • Hallucinations, delusions
  • Nightmares, vivid dreams, night terrors
  • Stalevo adds entacapone, a COMT inhibitor (see below), to the levodopa/carbidopa combination. Side effects are reported to be those described above, plus those listed below for entacapone.

    Dopamine Agonists

    Common names include:

        
  • Bromocriptine
  • Cabergoline
  • Pramipexole
  • Ropinirole
  • Apomorphine
  • Rotigotine patch
  • These drugs affect the brain in a way similar to dopamine. They may be given by themselves early in Parkinson’s disease, or along with other medications (like levodopa) later in the course of the disease. Dopamine agonists cause less motor fluctuations and dyskinesias due to the longer duration of action.

    Some people develop hallucinations or confusion while taking dopamine agonists and have to stop taking the medication. Do not use alcohol while you are taking a dopamine agonist. You will have unpleasant and potentially dangerous symptoms, including nausea, vomiting, fast heart rate, blurry vision, chest pain, headache, and extreme weakness.

    Possible side effects include:

        
  • Lightheadedness
  • Drowsiness
  • Dry mouth
  • Nausea, vomiting
  • Constipation
  • Headache
  • Ankle swelling
  • Sudden low blood pressure when you first stand up—which can result in falling
  • Sudden sleep attacks—these attacks can be very dangerous if they occur while you’re driving
  • Hallucinations, delusions
  • Compulsive gambling
  • Other Side Effects

    Apomorphine is a short acting dopamine agonist given as an injection in advanced cases. The medication was approved by the FDA for wearing-off spells. These spells occur in people who have been receiving long-term dopamine replacement therapy. The side effects are similar to that of the dopamine agonists, but nausea and vomiting have been reported to occur more often.

    Cabergoline has also been associated with the risk of serious heart damage. The dopamine agonist bromocriptine has rare, but significant, side effects (such as pericardial, pleural, and pulmonary fibrosis). Talk to your doctor if you have been taking these medications and are concerned about potential side effects.

    Monoamine Oxidase Type B Inhibitor

    Common brand names include:

        
  • Selegiline
  • Rasagiline
  • Selegiline and rasagiline are usually given along with levodopa or levodopa/carbidopa combinations. Both interfere with the breakdown of dopamine in the brain.

    You may have a severe reaction if you take this medication along with the opioid painkiller, meperidine.

    If you are taking selegiline at higher-than-usual doses, you may have a sudden, dangerous spike in blood pressure if you eat or drink things that contain a substance called tyramine. Tyramine is found in:

        
  • Aged cheeses
  • Beer, wine, and other alcoholic beverages
  • Smoked or pickled meats, chicken, fish, and cheeses
  • Caffeinated foods and beverages (colas, coffee, tea, chocolate)
  • Nonprescription remedies for colds, allergies, sinuses, cough, asthma, hay fever, and appetite control
  • Call your doctor right away if you notice:

        
  • Severe headache
  • Stiff neck
  • Chest pain
  • Abnormally fast or slow heartbeat
  • Severe nausea and vomiting
  • Increased sweating
  • Possible side effects include:

        
  • Dry mouth
  • Lightheadedness
  • Sudden low blood pressure when you first stand up—which can lead to falls
  • Difficulty sleeping
  • Nausea, vomiting (mild)
  • Visual hallucinations
  • Agitation
  • There are several medications that should not be taken while taking selegeline and rasasgiline. Some of these include:

        
  • Selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), and tricyclic antidepressants
  • Lienzolid, an antibiotic
  • Certain decongestants and stimulants, such as amphetamines, ephedrine, phylephrine, pseudoephedrine
  • Cyclobenzaprine
  • Dextromethorphan, a cough suppressant
  • Certain opioid analgesics, such as methadone, tramadol
  • Other monoamine oxidase (MAO) inhibitors
  • Anticholinergics

    Common names include:

        
  • Trihexyphenidyl
  • Benztropine
  • These medications can decrease tremor and stiffness and improve muscle control.

    You’ll have less chance of stomach irritation if you take these medications with food. Don’t take an anticholinergic medication within the hour after you’ve taken medication for diarrhea; the diarrhea medication will interfere with the actions of the anticholinergic medication. Don’t use alcohol while you're taking anticholinergic medications. Check with your doctor before using any medications that make you drowsy.

    Before you begin treatment with anticholinergic medications, get your eyes checked by an ophthalmologist.

    Possible side effects include:

        
  • Drowsiness
  • Lightheadedness
  • Sensitivity to bright lights
  • Dry mouth
  • Urinary retention
  • Blurred vision
  • Constipation
  • Fast heartbeat, palpitations
  • Mood changes
  • Memory difficulties
  • Confusion
  • Hallucinations
  • Amantadine

    Common brand name:

        
  • Amantadine
  • Amantadine can help reduce stiffness and tremor and improve muscle control. Sometimes this medication stops working after you’ve been taking it for a while. Your doctor may recommend that you take a break (a drug holiday) from the medication and then restart it. This may help the drug regain its effectiveness.

    Don’t drink alcohol while you’re using amantadine. If you begin to feel depressed or suicidal, talk with your doctor right away.

    Possible side effects include:

        
  • Lightheadedness, especially when first rising, which may increase risk of falling
  • Confusion
  • Blurry vision
  • Difficulty concentrating
  • Dry mouth
  • Purplish-red blotchy skin rash
  • Depression
  • Nightmares
  • Insomnia
  • Hallucinations
  • Urinary retention
  • Swelling in the lower extremities
  • Researchers are focusing on neuroprotective medications. These medications may be able treat the underlying problems causing Parkinson’s, not just the symptoms.

    Special Considerations

    If you are taking medications, follow these general guidelines:

        
  • Take the medication as directed. Do not change the amount or the schedule.
  • Ask what side effects could occur. Report them to your doctor.
  • Talk to your doctor before you stop taking any prescription medication.
  • Plan ahead for refills if you need them.
  • Do not share your prescription medication with anyone.
  • Medications can be dangerous when mixed. Talk to your doctor if you are taking more than one medication, including over-the-counter products and supplements.
  • When to Contact Your Doctor

        
  • The drug does not seem to be working.
  • You have undesired side effects.
  • You begin to have stomach problems while taking any medication.