neurodegeneration and epilepsy drugs

a patient with MS is prescribed interferon beta (Betaseron) what is a priority teaching at this time?

educate about self-injection technique

drugs that inhibit DA breakdown

**carbidopa Entacapone Tolcapone **Selegiling Rasagiline -used in combination therapy with levodopa to enhance so it does not metabolize so quickly in the small intestine

*Valproate*

-potentiate GABA -suppresses sodium and calcium channels adverse effects: *heptatoxicity* liver failure, pancreatitis, teratogenic DDI: phenobarbital, phenytoin, topiramate-monitor plasma levels carefully, avoid meropenem and imipenem/cilastatin antibiotics

antiseziures drugs and pregnancy

-pregnant women MUST continue their medications -fetal risk from seizures are greater than the meds -teratogenic :cause fetal abnormalities -some anti seizure drugs decrease the efficacy of birth control Carbamazepine Eslicarbazepine Oxcarbazepine Lamotrigine

centrally acting muscle relaxers for spasticity

*Baclofen* works in CNS *preferred over Dantrolene to preserve strength (tone) Diazepam -benzodiazepine GABA agonist (lights off) adverse: generalized CNS depression and GI upset, urinary retention, *physical dependence* withdrawal, overdose (respiratory depression) contraindications: CNS depressants: alcohol, opioids, benzos (fatal respiratory depression)

Centrally acting muscle relaxants for spasm

*Cyclobenzaprine* works in the CNS Diazepam -benzodiazepine GABA agonist (lights off) Tizanidine -alpha 2 agonist (cutting off sympathetic outflow) adverse effects: generalized CNS depression and GI upset, hepatic toxicity (tizanidine), *physical dependence* abstinence syndrome in babies, withdrawal contraindications -CNS depressants: alcohol, opioids, benzos (fatal respiratory depression)

immunosuppressants for MS

*Mitoxantrone Cladribine -more toxic, risk of infection, vaccine risk -chemotherapeutic agent (blocks DNA synthesis) adverse: *intense, myelosuppression, cardiotoxicity, fetal harm, alopecia, GI upset, blue-green tint to urine and skin

the nurse is caring for a patient who is receiving pramipexole (mirapex) the nurse is most concerned if the patient makes what statement?

"sometimes I just fall asleep without warning"

drugs that promote dopamine release

**Amantadine adverse effects: confusion, lightheadedness, anxiety, blurred vision, urinary retention, dry mouth, constipation, livedo reticular (mottled skin)

anticholinergics in PD

**Benzotropine Trihexyphenidyl -blockade of muscarinic receptors of the striatum -want less acetylcholine -less effective but better tolerated -BEERS: potentially inappropriate in geriatrics -adverse effects: anticholinergic side effects (hot as a hare, dry as a bone, mad as a hatter, blind as a bat, red as a beet)

cholinesterase inhibitors for Alzheimer's

**Donepezil Rivastigmine Galantamine -prevent breakdown of ACh (already have less levels. trying to keep up) -mild to moderate AD adverse: SLUDGE, headache, dizziness, bradycardia related falls, bronchoconstriction *caution with COPD and asthma DDI: anti-cholinergic agents, antihistamines, tricyclic antidepressants

Immunomodulators for MS

**Interferon beta 1-a -reduce inflammation, naturally occurring -injection, self injections, single use adverse: *flulike reactions, hepatotoxicity, myelosuppression, *injection site reactions, depression, suicidal thoughts, neutralizing antibodies Glatiramer Acetate *preferred, better tolerated, less effects -inhibits immune response to myelin basic protein adverse: *injection site reactions

neuronal receptor blocker for Alzheimer's

**Memantine -NMDA receptor antagonist -moderate to severe AD -prevents excessive stimulation adverse: dizziness, headache, confusion, constipation

non-ergot derivatives

**Pramipexole Ropinirole selective dopamine receptor agonist adverse: mono therapy (dizziness, nausea, insomnia, hallucinations, constipation) combo: (orthostatic hypotension, dyskinesia, hallucinations) caution in elderly. sleep attacks.

Antiseizure drugs

-suppress discharge of neurons within a seizure focus -suppress propagation of seizure activity from the focus to other areas of the brain (generalized seizure) mechanisms of action -suppression of sodium influx (going in) -suppression of calcium influx (going in) -promote potassium efflux (going out) -potentiation of GABA -antagonism of glutamate

classifications of antiseizure drugs/antieplieptic drugs (AEDs)

-Traditional AEDs *Phenytoin Fosphenytoin Carbamazepine Valproate Ethosuximide Phenobarbital Primidone New generation AEDs (more selective) *Oxcarbazepine Gabapentin Zonisamide

*Topiramate*

-antagonize glutamate -suppresses sodium and calcium channels -potentiates GABA Adverse effects: dizziness, ataxia, nervousness, diplopia, nausea, anorexia and weight loss, *metabolic acidosis* measures serum bicarb and monitor changes DDI: phenytoin and carbamazepine

drugs that antagonize glutamate

-block "lights on" New generation *Topiramate* Perampanel -antagonize glutamate receptors or decrease glutamate activity

drug classes for muscle spasm and spasticity

-centrally acting muscle relaxer for localized muscle spasm *Cyclobezaprine* Diazepam Tizanamide -centrally acting muscle relaxer for spasticity *Baclofen* Diazepam -direct acting muscle relaxer Dantrolene

levodopa/carbidopa/entacapone

-fixed dose combination (stalevo) -better than taking separate doses -only in immediate release tablets, only has three strengths (cant do fine adjustments)

blood brain barrier

-impedes entry of drugs into the brain -passage across is limited to lipid-soluble drugs

PD therapeutic goals

-increase dopamine -dopaminergic agents (work to promote dopamine or prevent breakdown) -anticholinergic agents (prevent more ACh)

common immunomodulator concerns (MS)

-neutralizing antibodies decreasing drug effects -hypersensitivity rxns -opporunistic infections (progressive multifocal leukoencephalopathy in Natalizumab) -hematologic changes -liver injury (monitor ALT and AST) -vaccine risk -generally not safe in children and pregnant women

drugs for muscle spasm and spasticity

-one group for localized muscle spasm -one group for spasticity most drugs produce their effects through actions in the CNS -exception: dantrolene (acts peripherally) these drugs are not interchangeable -exception: diazepam (can be used for spasm or spasticity)

Phenytoin

-suppress sodium influx -active against focal and tonic-clonic -narrow therapeutic window due to strange kinetics (hard to maintain dose without producing toxicity) -poor liver metabolism -half life depends on dose: 8 to 60 hours (10-20 mcg/mL) adverse effects: sedation, ataxia, diplopia, nystagmus, gingival hyperplasia (educate on oral hygiene and folic acid supplement), skin rash, effects in pregnancy (teratogenic, vitamin K can prevent bleeding in infant), severe Hypotension and dysrhythmias (admin quickly and large doses) prevent with slow IV admin and cardiac monitoring DDI: decreases effects of birth control, warfarin, glucocorticoids. increase levels (diazepam, isoniazid, cimetidine, alcohol, valproate) decrease levels (carbamazepine, phenobarbital, alcohol/chronic)

Oxcarbazepine

-supress sodium influx adverse effects: dizziness, drowsiness, ataxia, diplopia, nystagmus, headache, nausea, vomiting, *hyponatremia, skin reactions, Steven Johnson syndrome, toxic epidermal necrolysis DDI: *sodium depleting drugs and *alcohol, oral contraceptives less effective decrease levels (*phenytoin*, valproate, phenobarbital) increase levels (perampanel)

nursing considerations antiseizure drugs

-takes time to diagnose and requires record keeping seizure frequency charts (types of seizures), medication schedules, serum plasma levels -maintenence -patient compliance is critical : drugs need to be taken at regular intervals, stopping treatment is a decision made by the prescriber and must be done SLOWLY (tapered off)

Cannabidiol

-used as an AED for seizures -given orally in liquid form -adeverse: drowsiness, dry mouth, low blood pressure, diarrhea uses: dravet syndrome (fever sensitive myoclonic seizure in infants) lennox-gastaut syndrome (seizures in children that start between 3 and 5 years of age. patients also display intellectual and learning disabilities)

the nurse prepares to administer cholinesterase inhibitor to a patient with AD. which medication if ordered by the healthcare provider should the nurse question?

Amitriptyline (tricyclic depressant) rationale: blocks affects of the drug

ergot derivatives

Bromocriptine Cabergoline dopamine receptor agonist -mildly block serotonin and alpha receptors adverse: Nausea, *psychosis (confusion, nightmares, hallucinations)

drugs that increase potassium efflux

Ezogabine increase potassium efflux to reduce neuronal firing -not typically given long term adverse: dizziness, fatigue, confusion, vertigo, memory impairment, diplopia, retinal abnormalities, urinary retention and red-orange urine (not for patients with urinary retention), skin discoloration DDI: decrease levels by carbamazepine and phenytoin

dopamine agonist vs levodopa

Less effective than levodopa Not dependent on enzymatic conversion to be active Does not compete with dietary proteins Lower incidence of response failure in long- term use Less likely to cause dyskinesias Serious side effects

**Selegiline

Rasagiline -inhibit DA breakdown -inhibit MAO-B to enhance levodopa effects -mono or combo therapy adverse: can enhance levodopa effects **preferred combo over COMT inhibitors DDI: methyldopa, dobutamine, isoproterenol selegiline - insomnia, can build tolerance

drugs that suppress sodium influx (antiseizure meds)

Traditional *Phenytoin Fosphenytoin Carbamazepine (common) New Generation *Oxcarbazepine Topiramate Zonisamide Lacosamide Rufinamide -reduce seizures by decreasing sodium influx in hyper excitable neurons

drugs that potentiate GABA

Traditional *Valproate* Phenobarbital Primodone New Generation Topiramate Tiagabine Vigabatrin -increase GABA activity (lights off, shuts everything down)

drugs that suppress calcium influx

Traditonal *Ethosuximide* New Generation Pregabalin Topiramate Zonisamide -reduce seizures by decreasing calcium influx in hyper excitable neurons

the nurse prepares to administer dantrolene (dantrium) to a patient. before the administration of the drug, it is most important for the nurse to assess which laboratory value?

aminotransferases

CNS adaptation to prolonged drug exposure

antidepressants typically require 2-3 weeks to show mood improvement -give time morphine taken to control pain, nausea is common side effect early on, treatment continues and nausea diminishes but analgesic effects persist

an older patient with skin cancer and HTN is prescribed levodopa/carbidopa (sinemet) to treat Parkinson's disease. which action by the nurse is best?

ask the patient about the type of skin cancer rationale: not for patients with previous malignant melanoma, can activate it

most effective therapy for Parkinsons

carbidopa levodopa

drug therapy for Alzheimer's

cholinesterase inhibitors **Donepezil Rivastigmine Galantamine Neuronal NMDA receptor antagonist **Memantine

multiple sclerosis

chronic inflammatory autoimmune disorder that damages the myelin sheath of neurons in the CNS -impaired vision, slurred speech, numbness, muscle weakness, cognitive changes, back pain

the nurse is caring for a patient who is taking phenytoin (dilantin). which medication if ordered by the physician should the nurse question?

cimetidine (Tagamet) rationale: C4P inhibitor, boost into the toxic range

goal of anti seizure drugs

decrease hyper excitability by decreasing neuronal activity -potentiate GABA ("off" signal in the brain) neurotransmitter suppressant - antagonism of glutamate ("on" signal in brain) -suppress sodium influx -suppress calcium influx -promote potassium efflux

*Dantrolene*

direct acting muscle relaxers for spasticity -blocks calcium release from the sarcoplasmic reticulum to reduce skeletal muscle contraction adverse effects: muscle weakness, drowsiness, diarrhea, hepatotoxicity (caution in liver), acne-like rash

Dopamine receptor agonists

ergot derivatives (less selective) Bromocriptine Cabergoline Non-ergot derivatives (highly selective) **Pramipexole Ropinirole **first line of therapy in PD (others are hard to dose specifically and have bad adverse effects)

a patient is newly prescribed carbamazepine (tegretol) for seizure control. it is most important for the nurse to teach the patient to avoid which food?

grapefruit juice

drug therapy for MS

immunomodulators and immunosuppressants -decrease frequency and severity of relapses, reduce development of brain lesions, decrease future disability, help maintain quality of life -earlier preventing damage, better preservation of tissue

carbidopa

inhibits DA breakdown in periphery enhances levodopa effects decreases side effects, decreases amount metabolized in small intestine -adverse: can enhance levodopa effects

a patient taking levodopa/carbidopa (sinemet) for Parkinson disease experiences frequent "on-off" episodes. which action by the nurse is best?

instruct the patient to avoid high-protein foods

drugs for muscle spasm

muscle spasm: involuntary contraction of muscle or muscle group causes: epilepsy, hypocalcemia, pain syndromes:adult and chronic, trauma: localized skeletal muscle injury treatment of spasm: immobilization, cold compress. physical therapy, centrally acting skeletal muscle relaxant

Parkinson's disease

neurodegenerative disorder associated with disruption of neurotransmission in the striatum -dopaminergic neurons degenerate -decreases dopamine output -acetylcholine dominates

*Ethosuxamide*

preferred agent in absence seizures (Common in children) -suppress calcium influx adverse: drowsiness, dizziness, lethargy -no other significant adverse effects

carbamazepine

preferred agent in suppressing sodium influx -wider therapeutic window adverse effects: ataxia and nystagmus, leukopenia, anemia, thrombocytopenia, skin rash, Steven Johnsons syndrome, toxic epidermal necrolysis -teratogenic DDI: decreases effects of oral contraceptives, warfarin, glucocorticoids increase levels (grapefruit juice) decrease levels (phenytoin and phenobarbital)

disease modifying drugs I: immunomodulators MS

preferred over immunosuppressants (toxic) **Interferon beta Dimethyl fumarate Diroximel Fumarate Glatiramer Acetate (clinically) Natalizumab Fingolimod Teriflunomide Alemtuzumab

Levodopa

promotes dopamine synthesis -adverse effects: diminishing effect, N/V, dyskinesia (cant move), psychosis, darkens sweat and urine -activates malignant melanoma -given systematically, but can go into periphery -very little reaches the brain alone DDI: high protein foods, DA antagonists, non-selective MAOI

focal-onset seizures

small areas of activity -focal aware -focal impaired awareness (black out) -focal to bilateral tonic-clonic seizures (starts in specific area, progresses into a general tonic-clonic)

drugs for spasticity

spasticity: movement disorders of CNS origin causes: MS, cerebral palsy characteristics: heightened muscle tone (rigidity), spasms, loss of dexterity

a patient with multiple sclerosis is prescribed baclofen (Lioresal, Gablofen) which assessment by the nurse indicates that the medication is exerting its desired effect?

suppression of spasticity

a patient is prescribed phenytoin (dilantin) for epileptic seizures. which of the following is the priority for patient teaching?

teach the patient to avoid the abrupt cessation of treatment

**Entacapone

tolcapone (preferred) -drugs that inhibit dopamine breakdown -inhibits COMT to enhance levodopa effects adverse: can enhance levodopa effects Entacapone can cause N/V, diarrhea, constipation, yellow-orange urine DDI: methyldopa, dobutamine, isoproterenol

generalized-onset seizures

tonic clonic (contraction, convulsions) absence atonic (collapse, lose rigidity) myoclonic status epilepticus febrile

PD symptoms

tremor, rigidity, akinesia (loss or impairment in voluntary movement), posture (slumped over, poor balance) -depression, psychosis, dementia, autonomic disturbances