Module 3 - Anti- epileptic and Anti-Parkinson Medications Flashcards
what are sedatives and hypnotics
drugs that have a calming effect by inhibiting the transmission of nerve impulses to the central nervous system.
what do sedatives do?
reduce nervousness, excitability and irritability without causing sleep
what do hypnotics do?
cause sleep, stronger than sedatives
central and direct acting muscle relaxants:
indications
-relax skeletal muscles and relieve pain associated with central-acting skeletal muscle spasm.
Most effective when taken with physical therapy and rest
central and direct acting muscle relaxants:
Mechanism of Action
- work within the CNS to alter nerve transmission to brain, spinal cord, by working with GABA, a CNS inhibitor.
- Dantrolene acts at muscular level to inhibit nerve impulses (not in CNS) by decreasing amount of calcium released.
- Actions: sedative effect, relaxes muscle spasticity and rigidity.
central and direct acting muscle relaxants:
what should nurses know and teach pts
- Known contraindications: allergy, severe kidney impairment
Adverse effects: euphoria, lightheadedness, dizziness, drowsiness, fatigue, muscle weakness (short term).
unusual adverse effects: gastrointestinal problems, headache, slurred speech, hypotension (orthostatic), tachycardia, weight gain.
Muscle relaxant interactions
alcohol and other depressant drugs potentiate effects, may cause hypoglycemia
muscle relaxants types
central acting:
- baclofen
- cyclobenzaprine hydrochloride
- tizanidine hydrochloride
Direct acting:
-dantrolene sodium
what is the nursing process for muscle relaxants
1) assess: patient, allergies, vitals, contraindicating conditions (kidney impairment), LOC, breathing
2) Diagnoses:
- Risk for injury and falls, deficient knowledge
3) Plan
- Goals patient will be free from respiratory depression
4) Implementation
- avoid or e cautious with alcohol consumption and CNS depressants
5) Evaluation
- has spasm improves?
Seizure
-Brief episode of abnormal electrical activity in the nerve cells of the brain, may cause brief lapse in consciousness or (period of blankness, searching for words)
Convulsion
Involuntary spasmodic contractions of any or all voluntary muscles throughout the body, including skeletal and facial muscles, recurrent sensory disturbances, abnormal behaviours, or combination
Epilepsy
Chronic, recurrent seizures with or without a known cause.
- Brain injury, stroke ect
- Fibril seizures (in children due to temp)
Antiepileptic Drugs (AED) uses
all types of epilepsy management, anticonvulsants prevent seizures
- Long-term maintenance therapy for chronic, recurring seizures
- Acute treatment of convulsions and status epilepticus
- Other uses:
- neuropathic pain and phantom limb pain (gabapentin)
- mood stabilizers (carbamazepine)
- anxiety (lorazepam)
- panic disorders (clonazepam)
Antiepileptic Drugs (AED) Goals
control or prevent seizures while maintaining a reasonable quality of life
how long are patients on AED’s
lifelong therapy
Antiepileptic Drugs (AED): Mechanism of Action
unknown
- thought to alter movement of Na+, K+, Ca+ across brain neutrons
theories:
1) Reduce nerve’s ability to be stimulated
2) Suppress transmission of impulses from one nerve to the next
3) Decrease the speed of nerve impulse conduction within a neuron
seizures: tonic phase
elbows and heels on ground but back arched
seizures: clonic phase
rhythmic compulsions
Status epileptic
continuous seizure activity without a pause for 30 minutes or 2 back to back seizures (i.e. without an intervening period of normal brain function).
narrow therapeutic index
Safe and toxic levels are close
AED: Barbiturate (phenobarbital)
dose, indication, advantage
dose - Adult 90-120 mg at HS po
indications - simple, complex, generalized tonic-clonic, absence
advantage - Provides sedative hypnotic effects in addition to contol, prevention of seizures
AED: carbamazepine (Tegretol)
dose, indication, advantage, MOA
dose - 800-1,200 mg/day in 2-4 divided doses
indications - -partial seizures, tonic-clonic, trigeminal neuralgia, acute mania
Advantage - steady drug levels
MOA: decreases synaptic transmission in CNS by affecting sodium channels in neurons
AED: phenytoin (Dilantin):
dose, indication, advantage, MOA
dose - 300-400 mg/day for maintenance indications - tonic/clonic, status epilepticus advantages: -daily or BID dosing -parenteral form available -inexpensive
MOA: limits seizure propagation by altering ion transport, may also decrease synaptic transmission
AED: divalproex sodium (Epival):
dose, indication, advantage
dose: 750-1,000 mg/day in 2 divided doses
indications: multiple seizures, manic episodes, migraine prevention
advantages: broad spectrum, low incidence of rash, less cognitive effects than older AEDs
MOA: increase levels of GABA, an inhibitory neurotransmitter in the CNS
Nursing Implications for AED’s
pregnancy increases risk d/t probability of developing birth defects
- Take regularly, same time each day (steady levels)
- Take with meals to reduce gastrointestinal upset
- Do not crush, chew, or open extended-release forms
- abrupt withdrawal causes rebound seizures
- IV route given slowly with NS
- avoid extravasation (unintended leakage) of fluids - can cause blisters
- IV phenytonin always have filtered needle (caustic to tissues and could cause purple discolouration and deem of tissue
AED adverse effects
drowsiness, dizziness, nausea, vomiting, rash, urticaria,
Stevens-Johnson syndrome (slough off all your skin),
Dysrhythmias, heart failure, bone marrow depression,
Thrombocytopenia, peripheral edema
-mental status and mood changes, eye problems, visual disorders, sore throat, fever
Anticholinergic drugs
block or impede the activity of the neurotransmitter acetylcholine (Ach) at the cholinergic receptors in the brain.
Dopaminergic drugs
used to replace the deficiency of dopamine at dopamine receptors in the nerve endings, especially in the brain when treating Parkinson’s disease.
Parkinson’s Disease
a slowly progressive degenerative disease or neurological disorder characterized by resting tremour, pill-rolling, mask-like facies, shuffling gait, loss of postural reflexes, and muscle rigidity and weakness, Bradykinesia
-progresses from tremors, jerky head movements, shuffling gait, postural reflexes
-imbalance of dopamine (decreased) and ACh (increased):
symptoms don’t appear until 80% of dopamine is gone, leaving 20% dopaminergic terminals working
treatment: levodopa- can enter brain, form dopamine, and block ACh at dopaminergic terminals.
What kind of drug is used to treat parkinson’s disease?
Monoamine oxidase inhibitor
Parkinsons -
MAO-A Inhibitors:
interactions
cheese, wine, beer, yoghurt (not used often
parkinsons: MAO-B inhibitor
Selegiline used with levodopa to treat PD
parkinsons: MAO-B inhibitor
Mechanism Of Action:
Mechanism of action:
- increase levels of dopaminergic stimulation in CNS
-increases dopamine levels in brain, allowing dose of levodopa to be decreased.
Indirect dopamine agonist. Adult dose: 5 mg bid with breakfast and lunch.
contraindications for selegiiline
allergy, use of meperidine
MAO-B inhibitors:
Adverse Effects
nausea, lightheadedness, dizziness, abdominal pain, insomnia, dry mouth, confusion.
When dose is more than 10 mg per day, hypertensive crisis with consumption of tyramine containing food, memory loss, muscular twitches and jerks, grinding of teeth.
what are dopaminergics
provide exogenous replacement of dopamine to enhance the function of the few neurons that are still producing dopamine in brain
Dopaminergics:
MOA
depends on category
amantadine:
Release dopamine from remaining functional dopamine vesicles of neurons, or inhibit dopamine metabolizing enzymes
levodopa-carbidopa:
Provide exogenous dopamine in tablet form to increase brain levels of dopamine
bromocriptine, pramipexole (Mirapex), and ropinirole (ReQuip):
-Dopaminergic agonists that act as dopamine substitutes and stimulate dopamine receptors in place of dopamine
Parkinson’s:
Catechol Ortho-Methyl-Tranferase (COMT) inhibitors
- indication
- contraindication
- MOA
- interactions
- treat parkinsons
- Contraindications: allergy to dopaminergic drugs, history of melanoma or known skin condition, narrow-angle glaucoma.
- MOA: Inhibit the breakdown of levodopa in peripheral circulation, and prolongs the effect of levodopa, with less wearing off phenomenon. (pre-synaptic or indirect acting)
- interactions: CNS drugs
what do anticholinergic drugs do to treat parkinson’s disease
Block the effects of acetylcholine, can be useful in treating muscle tremours and rigidity (caused by excess ACh)
anticholinergic drugs and their adverse effects
MOA
belladona alkaloids, atropine and scopolamin
adverse effects: dry mouth, urinary retention, and blurred vision
MOA: block acetylcholine pathways in brain.
symptoms of excess Ach and how are these reversed
SLUGE S-salavation L - lacrimation U- urination D - diarrhea G - gastrointestinal motility E - emesis.
*Anti-cholinergic drugs block these effects
Anticholinergic drugs act on basal area of ganglions to help stop acetocholine from being produced so much to reduce tremors
anticholinergic drugs
contraindications, adverse effects, and interactions
contraindications: allergy, glaucoma, gastric or bladder outlet obstruction, heart disease, and myasthenia gravis
adverse effects:
- CNS: drowsiness, confusion, disorientation, hallucinations
- Gastrointestinal: Constipation, nausea, vomiting
- Genitourinary: Urinary retention, pain on voiding
- Other: blurred vision, dilated pupils, photophobia, dry skin
interactions: additive effects c/ alcohol, CNS depressants, amantadine, phenothiazine, tricyclic antidepressants, and antihistamines
ph change in stomach and delayed absorption caused by antacids
nursing interventions with parkinson drugs
- Assist with ambulation (messing with movement centre)
- give oral doses with food
- Vitamin B6 10 mg - reverse effects of levodopa and should be avoided.
- encourage extra fluid and a high finer diet
- give doses hours before bed as it can cause insomnia
Which of the following reflects the most appropriate nursing action for IV phenytoin (Dilantin) administration?
A. ensure continuous infusion of the drug
B. give IV doses via rapid IV push
C. administer in dextrose solutions
D. administer in normal saline solutions
D. administer in normal saline solutions
Which of the following is the most appropriate when administering an antiepileptic drug?
A. take on an empty stomach
B. take at the same time every day
C. crush tablets if unable to swallow
D. stop if seizure activity disappears
B. take at the same time every day
A patient with parkinson’s disease is not responding well to levodopa (single source drug that is a dopomine substance). The physician adds carbidopa to prevent peripheral destruction of levodopa and result in increased amounts of levodopa to the brain.
True or False
true
