shift is wild

Pharmacology · chapter 11 · Drugs to Treat Parkinson’s Disease and Multiple Sclerosis

Introduction to Parkinson’s Disease

The 14 things this section of the textbook says that you are most likely to be asked about — quoted word for word, not retold. Then 6 practice questions with the reasoning.

Skip to the questions ↓

Key points

  1. What Parkinson's disease destroys

    Parkinson’s disease (PD) is a progressive neurologic condition that destroys some of the dopamine-secreting neurons of the substantia nigra, a critical area of the brain that produces dopamine and has an important role in controlling an individual’s movements.

  2. Antipsychotics can cause parkinsonism

    Parkinson-like symptoms may arise because of antipsychotic drugs. Antipsychotics block dopamine receptors, interfering with the same neural pathway and functions affected by the insufficient amount of dopamine.

  3. Lewy bodies

    In PD, neurons in the substantia nigra begin to atrophy, become impaired, or die; some contain Lewy bodies, which are alpha-synuclein protein aggregates that impair transport of dopamine and contribute to neuronal death.

  4. Too little dopamine, too much ACh

    People with PD have an imbalance that results in a decrease in dopamine and an excess of ACh. With the lack of dopamine, the excitatory ACh is the dominant neurotransmitter.

  5. No single diagnostic test

    Currently, no single definitive test exists to diagnose PD.

  6. Motor symptoms appear late

    Motor symptoms of PD occur late in the disease process. Usually 60%–80% of the dopamine-releasing neurons of the substantia nigra are already destroyed before the onset of motor symptoms (Parkinson’s Foundation, 2023e).

  7. Resting tremor and pill rolling

    Tremors are seen when the body is at rest and disappear upon purposeful movement or during sleep. “Pill rolling” is a classic behavior.

  8. Cogwheel rigidity

    During passive range of motion, there is resistance and the client exhibits jerky movements, also known as cogwheel rigidity. The tongue and throat may become involved, leading to difficulty swallowing and talking.

  9. Bradykinesia

    Clients with PD have difficulties initiating movement, such as walking or getting up out of a chair. Additionally, they have difficulty controlling fine muscle movements due to the loss of dexterity.

  10. Masked face

    Also, clients usually present with an expressionless face or flat affect due to facial rigidity. Blinking of the eyes is minimal.

  11. Postural instability and falls

    They do not have postural reflexes, so making corrective adjustments is challenging. The result is impaired balance and increased risk of falls.

  12. Choking and nutrition risk

    Food and saliva may collect in the mouth and back of the throat, which can result in choking or drooling. It may be difficult for the client to obtain adequate nutrition.

  13. Goal of drug therapy

    The overall goal of medication is to maximize independence and mobility. With PD, there is too little dopamine and too much ACh, so the approach to treatment is to restore the balance between the two neurotransmitters.

  14. Deep brain stimulation

    Deep brain stimulation has been found to be effective in reducing tremors, bradykinesia, and rigidity. A pulse generator sends controlled electrical signals to electrodes surgically implanted in the brain.

Terms to know

micrographia
Their writing becomes small and cramped, which is referred to as micrographia.
akinesia
Bradykinesia may progress to akinesia, which is the inability to move.
cogwheel rigidity
During passive range of motion, there is resistance and the client exhibits jerky movements, also known as cogwheel rigidity.
Lewy bodies
In PD, neurons in the substantia nigra begin to atrophy, become impaired, or die; some contain Lewy bodies, which are alpha-synuclein protein aggregates that impair transport of dopamine and contribute to neuronal death.

Practice questions

Stuck on select-all-that-apply? How to take them one option at a time.

The graded version needs JavaScript. Every question is below anyway, with the answer and why.

Every question here, with the answer

  1. A nurse observes a client with Parkinson's disease rubbing the thumb and forefinger together while sitting quietly. What happens to this tremor when the client reaches for a cup?

    1. It turns into cogwheel rigidity.
    2. It usually disappears with the purposeful movement.
    3. It spreads to both legs.
    4. It gets much worse.

    Answer: It usually disappears with the purposeful movement.

    Parkinson's tremors are resting tremors: they appear at rest and disappear with purposeful movement or during sleep. The other options describe changes the section does not link to purposeful movement.

  2. A client with Parkinson's disease has food and saliva pooling in the back of the throat during meals. Which risk is the nurse's priority?

    1. Choking
    2. Oily skin
    3. Resting tremor
    4. Micrographia

    Answer: Choking

    Food and saliva collecting in the mouth and throat can cause choking or drooling and makes nutrition difficult, so airway safety is the priority. Micrographia, tremor and oily skin are real features but do not threaten the airway.

  3. The nurse assesses a client with advancing Parkinson's disease. Which findings are consistent with the disease? Select all that apply.

    1. Expressionless face with minimal blinking
    2. Jerky resistance during passive range of motion
    3. Long strides with a wide arm swing
    4. Small, cramped handwriting
    5. Soft, monotone speech

    Answer: Expressionless face with minimal blinking, Jerky resistance during passive range of motion, Small, cramped handwriting, Soft, monotone speech

    Cogwheel rigidity, micrographia, masked face and soft monotone speech are all described manifestations. Clients with PD take small, quick steps with a reduced arm swing, not long strides.

  4. A client with schizophrenia who takes an antipsychotic develops a stooped posture, shuffling gait and muscle rigidity. What best explains this?

    1. The drug destroys norepinephrine nerve endings.
    2. The drug increases dopamine release.
    3. The drug causes Lewy bodies to form.
    4. The drug blocks dopamine receptors.

    Answer: The drug blocks dopamine receptors.

    Antipsychotics block dopamine receptors, interfering with the same pathway affected in PD, and can produce parkinsonism. They do not increase dopamine, and the section does not link them to norepinephrine loss or Lewy bodies.

  5. A nurse is planning care for a client with Parkinson's disease who has postural instability. Which interventions fit the section? Select all that apply.

    1. Implement fall precautions.
    2. Consider tai chi or yoga to improve strength and flexibility.
    3. Refer to speech therapy for safe swallowing.
    4. Encourage the client to stay in bed to avoid falls.
    5. Refer to physical therapy to stay as active as possible.

    Answer: Implement fall precautions., Consider tai chi or yoga to improve strength and flexibility., Refer to speech therapy for safe swallowing., Refer to physical therapy to stay as active as possible.

    Loss of postural reflexes raises fall risk; physical therapy, speech therapy for swallowing, and tai chi or yoga are listed nonpharmacologic strategies. Keeping the client in bed works against the goal of staying active and maintaining mobility.

  6. A student asks why Parkinson's drugs include both dopamine agonists and anticholinergics. Which explanation is correct?

    1. Anticholinergics raise dopamine production in the substantia nigra.
    2. PD causes too little dopamine and too much acetylcholine, and treatment restores the balance.
    3. PD causes too much dopamine and too little acetylcholine.
    4. Both drug types cure the disease by regrowing neurons.

    Answer: PD causes too little dopamine and too much acetylcholine, and treatment restores the balance.

    In PD there is too little dopamine and too much ACh, so treatment restores the balance with dopamine agonists and with anticholinergics that block ACh receptors. The drugs reduce symptoms; they do not cure or regrow neurons.

Where every quote comes from

Section 11.1 Introduction to Parkinson’s Disease of Pharmacology for Nurses by Tina Barbour-Taylor, Leah Mueller (Sabato), Donna Paris, Dorie Weaver, OpenStax, 2024. Read the whole section free at openstax.org.

The textbook is licensed under CC BY-NC-SA 4.0. This page quotes it word for word and adds the headings, the order and the practice questions; references to the book's figures and stray spaces left by its formatting are removed. The page is shared under the same licence. Nothing here is sold.