Ch. 15 Antiparkinson Drugs

Catechol Ortho - Methyltransferase (COMT) Inhibitors Interaction

Prolong the duration of action of levodopa; reduce wearing-off phenomenon

anticholinergic therapy MOA

- Anticholinergics block the effects of ACh

Catechol Ortho-Methyltransferase (COMT) Inhibitors

- Block COMT, the enzyme that catalyzes the breakdown of the body's catecholamines

Parkinson's disease

- Chronic, progressive, degenerative disorder - Affects dopamine-producing neurons in the brain - Caused by an imbalance of two neurotransmitters: Dopamine Acetylcholine (ACh)

Treatment of Parkinson's Disease

- Full explanation of disease to the patient - Treatment centers on drug therapy - PT, OT, speech therapy important - Severe cases: Deep brain stimulation

Catechol Ortho-Methyltransferase (COMT) Inhibitors

- GI upset - urine discoloration - can worsen dyskinesia that may already be present - Tolcapone has been associated with cases of severe liver failure.

response to drug therapy

- Improved sense of well-being and mental status - Increased appetite - Increased ability to perform ADLs, to concentrate, and to think clearly - Less intense parkinsonian manifestations, such as less tremor, shuffling gait, muscle rigidity, and involuntary movements

Parkinson's disease symptoms

- Tremor - Rigidity - Akinesia - Postural instability •TRAP acronym - Staggering gait - Drooling

Selective MAO-B inhibitors

- cause an increase in levels of dopaminergic stimulation in the CNS - Do not elicit the "cheese effect" of the nonselective MAOI's used to treat depression (if 10 mg or less is used)

Nondopamine dopamine receptor agonists (NDDRAs) types:

- ergot derivatives - Nonergot drugs

Direct-Acting Dopamine Receptor Agonists two classes

- nondopamine dopamine receptor agonist (NDDRA's) - dopamine replacement drugs

Two types of dyskinesia

Chorea dystonia

anticholinergics have the opposite effects of Ach which are

dry mouth decreased salivation urinary retention decreased GI motility (constipation) dilated pupils (mydriasis) smooth muscle relaxation

Chorea

irregular, spasmodic, involuntary movements of the limbs or facial muscles

anticholinergic therapy is used to treat

muscle tremors and muscle rigidity associated with PD (These two symptoms are caused by excessive cholinergic activity.) - doesnt relieve bradykinesia

Ach is responsible for increased: (SLUDGE)

salivation lacrimation urination diarrhea GI motility inc emesis

Symptoms can be partially controlled as long as

there are functioning nerve terminals that can take up dopamine.

Nondopamine dopamine receptor agonists (NDDRAs) types: MOA

work by direct stimulation of presynaptic and/or postsynaptic dopamine receptors in the brain.

Nursing Implications

-Perform a thorough assessment, nursing history, and medication history -Include questions about the patient's: CNS GI and GU tracts Psychologic and emotional status - s/s of PD masklike expression dysphagia rigidity of arms, legs and neck - assess conditions for contraindications - do not take other meds w PD drugs unless pt checks w physician - assist pt w walking - give oral doses w food - encourage fluids (3000 ml a day) - do not discontinue abruptly

Symptoms of parkinson's disease occur when

80% of the dopamine stored in the substantia nigra of the basal ganglia is depleted.

Which drug used for the management of the patient with PD is most likely to cause postural hypotension? A. Amantadine (Symmetrel) B. Selegiline (Eldepryl) C. Tolcapone (Tasmar) D. Entacapone (Comtan)

A. Amantadine (Symmetrel) Amantadine, carbidopa-levodopa, and ropinirole are most likely to cause postural hypotension.

The patient diagnosed with PD has been started on dopaminergic replacement drug therapy with carbidopa-levodopa. 2. What is a priority action for the nurse? A.Assess the patient for dizziness and syncope when the patient is walking. B.Administer the medication first thing in the morning. C.Administer the medication on an empty stomach. D.Omit protein from the patient's diet.

A. Assess the patient for dizziness and syncope when the patient is walking.

A patient has been diagnosed with PD. Medication therapy is started for this patient. 1. What teaching should the nurse include to the patient and caregiver regarding pharmacologic therapy of PD? A. The medication should be stopped when the patient's symptoms improve. B. Alcohol, over-the-counter drugs, and herbals are to be avoided unless approved by the prescriber. C. A common side effect of anticholinergics is drooling. D. Improvements in symptoms are expected within 5 days of medication therapy.

B. Alcohol, over-the-counter drugs, and herbals are to be avoided unless approved by the prescriber.

How can the nurse best explain the "off-on phenomenon" that some patients with PD experience? A.The need to take a drug holiday to improve response to medications B.The variable response to levodopa, resulting in periods of good control and periods of poor control of PD symptoms C.The alternating schedule of medications needed to control PD D.The fluctuation of emotions that often occurs with PD

B.The variable response to levodopa, resulting in periods of good control and periods of poor control of PD symptoms Some patients who take levodopa on a long-term basis experience times when their PD symptoms are under control and other times when symptoms are not well controlled.

When providing teaching to a patient receiving an anticholinergic for the treatment of PD, the nurse will include which information? A.Take the medication first thing in the morning. B.Limit fluid intake when taking this drug. C.The tremors you experience will be reduced within 24 hours of taking this drug. D.Do not take this medication at the same time as other medications.

D. Do not take this medication at the same time as other medications. When anticholinergics are used for the treatment of PD, these medications should not be taken at the same time as other mediations. The medications should be administered at bedtime. Fluid intake should not be restricted as they cause dry mouth, and it may take several days to weeks for the beneficial effects of the medication to become evident.

The patient has now been ordered an oral disintegrating form of the MAO-B inhibitor drug selegiline. 3. What should the nurse consider when administering this drug? A.Tell the patient to take the medication with liquids. B.Tell the patient to take the medication with a meal. C.Assess the patient for hypertension, a common side effect of this medication. D.Tell the patient to place oral disintegrating dosage forms on the tongue, and do not swallow dosage form until it is completely melted.

D. Tell the patient to place oral disintegrating dosage forms on the tongue, and do not swallow dosage form until it is completely melted.

When assessing the medication history of a patient with a new diagnosis of Parkinson's disease, which conditions are contraindications for the patient who will be taking carbidopa-levodopa? (Select all that apply.) a. Angle-closure glaucoma b. History of malignant melanoma c. Hypertension d. Benign prostatic hyperplasia e. Concurrent use of monoamine oxidase inhibitors (MAOIs)

a. Angle-closure glaucoma b. History of malignant melanoma e. Concurrent use of monoamine oxidase inhibitors (MAOIs)

A patient taking entacapone (Comtan) for the first time calls the clinic to report a dark discoloration of his urine. After listening to the patient, the nurse realizes that what is happening in this situation? a. This is a harmless effect of the drug. b. The patient has taken this drug along with red wine or cheese. c. The patient is having an allergic reaction to the drug. d. The ordered dose is too high for this patient.

a. This is a harmless effect of the drug.

Dystonia

abnormal muscle tone leading to impaired or abnormal movements

While a patient is receiving drug therapy for Parkinson's disease, the nurse monitors for dyskinesia, which is manifested by which finding? a. Rigid, tense muscles b. Difficulty in performing voluntary movements c. Limp extremities with weak muscle tone d. Confusion and altered mental status

b. Difficulty in performing voluntary movements

The nurse is developing a care plan for a patient who is taking an anticholinergic drug. Which nursing diagnosis would be appropriate for this patient? a. Diarrhea b. Urinary retention c. Risk for infection d. Disturbed sleep pattern

b. Urinary retention

A patient has been taking selegiline (Eldepryl), 20 mg/day for 1 month. Today, during his office visit, he tells the nurse that he forgot and had a beer with dinner last evening, and "felt awful." What did the patient most likely experience? a. Hypotension b. Hypertension c. Urinary discomfort d. Gastrointestinal upset

b. hypertension

Indirect acting dopaminergic drugs: Monoamine Oxidase Inhibitors MAOI's

break down catecholamines in the CNS, primarily in the brain

The nurse is assessing the medication history of a patient with a new diagnosis of Parkinson's disease. Which condition is a contraindication for the patient, who will be taking tolcapone (Tasmar)? a. Glaucoma b. Seizure disorder c. Liver failure d. Benign prostatic hyperplasia

c. Liver failure

When treating patients with medications for Parkinson's disease, the nurse knows that the wearing-off phenomenon occurs for which reason? a. There are rapid swings in the patient's response to levodopa. b. The patient cannot tolerate the medications at times. c. The medications begin to lose effectiveness against Parkinson's disease. d. The patient's liver is no longer able to metabolize the drug.

c. The medications begin to lose effectiveness against Parkinson's disease.

Carbidopa-levodopa (Sinemet) is prescribed for a patient with Parkinson's disease. The nurse informs the patient that which common adverse effects can occur with this medication? a. Drowsiness, headache, weight loss b. Dizziness, insomnia, nausea c. Peripheral edema, fatigue, syncope d. Heart palpitations, hypotension, urinary retention

d. Heart palpitations, hypotension, urinary retention

A patient has been treated with antiparkinson medications for 3 months. What therapeutic responses should the nurse look for when assessing this patient? a. Decreased appetite b. Gradual development of cogwheel rigidity c. Newly developed dyskinesias d. Improved ability to perform activities of daily living

d. Improved ability to perform activities of daily living

A patient has a new order for a catechol ortho-methyltransferase (COMT) inhibitor as part of treatment for Parkinson's disease. The nurse recognizes that which of these is an advantage of this drug class? a. It has a shorter duration of action. b. It causes less gastrointestinal distress. c. It has a slower onset than traditional Parkinson's disease drugs. d. It is associated with fewer wearing-off effects.

d. It is associated with fewer wearing-off effects.

When a patient is taking an anticholinergic such as benztropine (Cogentin) as part of the treatment for Parkinson's disease, the nurse should include which information in the teaching plan? a. Minimize the amount of fluid taken while on this drug. b. Discontinue the medication if adverse effects occur. c. Take the medication on an empty stomach to enhance absorption. d. Use artificial saliva, sugarless gum, or hard candy to counteract dry mouth.

d. Use artificial saliva, sugarless gum, or hard candy to counteract dry mouth.

dyskinesia

difficulty in performing voluntary movements