Unit 3 - CNS meds Flashcards
How is status epilepticus treated?
IV benzo - usually Valium
Gabapentin / Pregabalin (Lyrica)
MOA: Activate GABA receptors to calm the body down (seizure activity); also reduces neuropathic pain.
Side effects: Fatigue, dizziness, ataxia, nystagmus, peripheral edema.
Considerations: No abrupt withdrawal (same as any seizure med). Start with lower dose and work up high.
Overdose s/s: Fatigue, diarrhea, slurred speech.
Phenytoin (Dilantin)
MOA: Stabilize neurons and decrease speed of conduction; block sodium/calcium channels.
Side effects: HOT MAIL G AND K - hirsutism(hormone changes)/hepatotoxicity; osteomalacia; teratogenicity; megaloblastic anemia; inhibits insulin release (pancreatitis); lymphadenopathy (lymph swelling); gum hypertrophy/hyperplasia; ataxia; nystagmus; diplopia (double vision), vitamin K deficiency; also bradycardia because it’s blocking those channels.
Considerations:
1. Small therapeutic index - monitor labs.
2. keep Good oral hygiene because of those side effects.
3. Monitor vitamin K levels.
4. Monitor liver function.
5. Don’t give this in pregnancy, liver failure, cardiac conditions, or diabetes
Valproic Acid (Depakene) / Divalproex Sodium (Depakote)
MOA: Stabilize neurons and decrease speed of conduction; block sodium/calcium channels (same as Dilantin)
Side effects: GI upset, drowsiness, tremors, ataxia, hair loss, teratogenicity, bradycardia because it’s blocking the sodium/calcium channels.
Considerations: Don’t give in pregnancy or heart conditions. Small therapeutic index so keep up with labs.
Carbamazepine (Tegretol)
MOA: Block sodium channels to reduce tonic-clonic seizure activity or trigeminal nerve pain.
Side effects: dizziness/drowsiness, hepatotoxicity, pancreatitis (pancreas toxicity), Steven Johnsons/toxic epidermal necrolysis, heart failure/edema/heart block, bone marrow issues - agranulocytosis/aplastic anemia/leukopenia, photosensitive, nystagmus, ataxia, psychotic behavior/suicidal thoughts.
Considerations: 1. Don’t give to patients with liver / pancreatic / cardiac issues. Monitor liver and pancreatic enzymes throughout treatment for normal people.
2. Monitor for symptoms of heart failure / heart block
3. Monitor CBCs and bone marrow deficiency symptoms (bleeding, infection, fatigue)
4. Don’t give to patients at high risk for suicidal behaviors or patients with bipolar. Monitor for behavioral changes.
5. Teach patient to wear sunblock - teach s/s of TENs and Steven-Johnson. Consult HCP if rash occurs
Barbiturates (Phenobarbital)
MOA: Activate GABA receptors - calming the body; blocking calcium channels; opening chloride channels - all to reduce seizures
Side effects: Bradycardia due to blocking the channels, respiratory depression, headache, sedation, hyperkinesia (movement), slurred speech, skin reactions (Steven-Johnson’s), cognitive impairment, anemia.
Considerations:
1. Can reduce the effects of some other drugs so check interactions before giving.
2. Can cause folate deficiency, which can cause anemia and may not be best in pregnancy.
3. Teach s/s of TENs and Steven-Johnson’s - consult HCP if rash occurs.
4. Don’t give to patients at risk for respiratory depression (COPD, asthma) but can actually be given to children
Considerations for all Parkinson’s meds:
- Ensure meds can be crushed for patients with swallowing difficulties or dysphagia
- NO alcohol can be given with these
- they are known to cause constipation so take precautions and education for that
- and the dosing with Parkinson’s is tough - On-off syndrome and wearing off syndrome may occur
Levodopa-Carbidopa (Dopamine replacement)
MOA: Increase dopamine levels.
Side effects: GI upset - N/V, anorexia, orthostatic hypotension, cardiac arrhythmias.
Considerations: Lots of drug-drug interactions. Levodopa when used alone causes a lot of N/V, so Carbidopa actually helps balance it out. Contraindications in cardiac abnormalities. Slow position changes because of hypotension.
*Go slow with levooo or you’ll go low
Benztropine aka Cogentin (Anticholinergic agents)
MOA: Decreases acetylcholine levels.
Side effects: typical anticholinergic drying effects - drowsiness/sedation, dry mouth/eye/nose, urinary retention + tachycardia.
Considerations: No glaucoma, HTN, MG, or elderly patients.
Donepezil (Cholinesterase inhibitors)
MOA: Actually inhibits the breakdown of acetylcholine by inhibiting cholinesterase, which increases memory, so this may be used more for the dementia-Parkinson’s combo and even in Alzheimer’s.
Side effects: typically just GI upset - N/V/D.
Considerations: May be altered response in CYP genetic mutations, so we do check those when giving this. That’s really it - it’s a pretty tame drug.
**Donezepil’s a really chill pill, just GI upset and my Parkinson’s is done
COMT inhibitors (Entacapone)
MOA: Block COMT which is the enzyme that breaks down dopamine in the brain, so it really inhibits the breakdown of dopamine and increases dopamine - often combined with Levodopa.
Side effects: GI upset (N/V), Postural hypotension, dizziness/drowsiness, orange urine.
Considerations: Slow position changes; Also, entacapone can cause urine to be very bright orange so just educate the patient on that.
Benzodiazepines (Diazepam aka Valium, Lorazepam aka Ativan, Clonazepam aka Klonopin, Alprazolam aka Xanax)
MOA: Strengthens receptor affinity for GABA (increasing GABA levels) - calming the system down.
Uses: Anxiety, seizures, alcohol withdrawal.
Side effects: GI upset, dizziness/drowsiness, headache, rash, lethargy, depression, resp. depression, constipation/weight gain; paradoxical excitation.
Considerations:
1. No alcohol since most of these have CNS depressing effects.
2. Watch for and educate on paradoxical reactions in which it does the opposite of what it’s supposed to do
3. Use cautiously in h/o depression or respiratory issues.
4. Discontinue before surgery and MRIs.
Clonazepam aka Klonopin
Special notes: Besides anxiety and seizures, it is used to mitigate s/s of alcohol withdrawal; Can cause amnesia, ataxia, and paradoxical reactions.
Mood stabilizers (Lithium)
MOA: Affects sodium transport across cell membranes.
Uses: Bipolar disorder.
Side effects: LITH - leukocytosis, insipidus (diabetes insipidus), tremor/teratogenic, hypothyroidism (long-term use) + GI upset.
Considerations:
1. NO pregnancy.
2. Very narrow therapeutic window (0.6-1.5 mmol/L), so watch for toxicity and overdose s/s (severe GI problems, tremors, cardiac arrhythmias and cardiac death) - it’s extremely toxic and lethal in an overdose. Trough levels are drawn 12 hours after the last dose regularly. Treatment for overdose: hemodialysis.
3. Long-term use watch for thyroid issues.
4. Avoid sudden changes in diet or fluid intake.
Considerations for all antidepressants:
- No alcohol with any of these.
- Drug interactions between each class; for example SSRIs and tricyclics don’t get along well so usually not prescribed in combination.
- Watch for suicidal ideations and mood shifts in the first few weeks of therapy. They can take a couple of weeks to have positive effects.
Selective serotonin reuptake inhibitors (SSRIs - Fluoxetine/Prozac, Sertraline/Zoloft, Proextine/Paxil, Escitalopram/Lexapro)
MOA: Inhibits re-uptake of serotonin into the nerve cell, so more serotonin sits in the synapse and connects with the receptors.
Uses: Anxiety, depression, OCD.
Side effects: Headache, dizziness/drowsiness, GI upset, lethargy/depression, sexual dysfunction (lower libido), weight gain.
Considerations: Watch for Serotonin Syndrome. No NSAIDs or anticoagulants with any of these because of bleeding risks.
Bupropion (Wellbutrin and Zyban):
Special notes: Used for Anxiety, depression, OCD + Smoking withdrawal. Same considerations and side effects as the others.
Tricyclic antidepressants (Amitriptyline, Doxepin, Amoxipine, etc)
MOA: We are not sure how they work! They have some kind of opioid type effects and interfere with the re-uptake of serotonin, kind of like SSRIs.
Side effects: Opioid-like effects - sedation, orthostatic hypotension, dry mouth, urinary retention, cardiac dysrhythmias.
Considerations: May be contraindicated in cardiac abnormalities and potentially elderly people because of those anticholinergic/opioid-like effects.
**amitriptyline is like an anticholinergic - no cardiac or elderly patients; they cause sedation/hypotension/retention.
MAO Inhibitors / MAOIs (Nardil, Parnate, Marplan)
MOA: Inhibits MAO enzymes that remove neurotransmitters from the brain, thus increasing overall neurotransmitter levels in the brain.
Side effects: dizziness, drowsiness, headache, GI Upset - the usual. Not too many serious side effects.
Considerations:
- Watch for Serotonin syndrome.
- These meds don’t play well with any medications, so really do not give these if the patient is taking any other meds, even OTCs.
- If you discontinue the MAOI, you have to take a 14 day washout before taking any other med that would interact badly with it.
- No tyramine foods (aged cheeses, meats, chocolate, coffee, cola, tea) while on this, just like anti-tubercular medications.
Serotonin syndrome S/S:
Tremors, grinding teeth, rhabdomyolysis, fever, diaphoresis, tachycardia, blood pressure spike or drop, agitation, confusion, delirium, hallucinations.
1st generation antipsychotics (Haloperidol/Haldol)
MOA: Block dopamine receptors to improve positive (behavioral) symptoms - overall DECREASING dopamine.
Uses: Mania, schizophrenia, behavioral disturbances in children. Can even be used as potent antiemetics.
Side effects: Drowsiness, dizziness, GI upset. Can actually cause psychosis + Extrapyramidal symptoms (smacking lips), tardive dyskinesia (excessive movements), neuroleptic malignant syndrome
Considerations: Watch for s/s of EPS, TD, or NMS.
Neuroleptic malignant syndrome
potentially life-threatening condition caused by antipsychotics that affect dopamine receptors in the brain. It’s characterized by a combination of symptoms including high fever, muscle rigidity, altered mental status, tachycardia, and unstable BP. This can mimic Serotonin syndrome.
Chlorpromazine
1st gen antipsychotic that can also cause agranulocytosis and photosensitivity. This one doesn’t cause the NMS that Haldol does.
2nd generation antipsychotics (Seroquel, Olanzapine, Risperidone, Aripriprazole/Abilify)
MOA: Not well known. They work on both positive and negative symptoms of psychosis.
Uses: Schizophrenia in adults mainly; Tourette’s syndrome; can be used as add-ons for depression or bipolar.
Side effects: Hypoglycemia, stroke, cardiac changes/arrhythmias/tachycardia, agitation, anxiety, insomnia, metabolic syndrome, weight gain.
Considerations:
1. Don’t give this in renal impairment and hepatic impairment. Not used often in elderly patients for this reason.
2. Cautious use in diabetes because of hypoglycemia.
3. Cautious use in recent stroke patients.
4. Don’t use in patients with cardiac issues.
5. Food interactions with Risperidone and coffee/cola/tea
**Seroquel makes my stomach fill; weight gain and anxiety, kidney/liver’s not happy! Food interactions with the cola - abilify is not for stroke ya.
