Neuropharmacology Flashcards
Parkinson’s drugs
Levodopa Carbidopa Pramipexole Entacapone Selegiline
Levodopa
- absorbed by GI System and peripheral tissues
- always combined with carbidopa or carbidopa/entacapone
- levodopa given by itself = 2% absorption in brain & 98% in GI causing the SA (ex: n/v)
- give with carbidopa to decrease SA
- NO FOOD w/ INCREASED SALT (avoid high salt)
- AVOID high PROTEIN meals
- “LevoDDDDopa!!” DDDD (adverse reactions: dose dependent, dyskinesias, dark urine and sweat, dyrhythmias)
Class: Dopamine replacement
MOA: converted to dopamine, activates dopamine receptors
D/R: PO, either with carbidopa or carbidopa and entacapone
ADR: (DDD) - dose dependent, dyskinesias, dark urine and sweat.
Early effects of treatment: insomnia, postural hypotension,
Interactions: carbidopa and entacapone increase effects, first gen antipsychotics decrease effects, MAOI increase toxicity, risk for hypertensive crisis
Contraindications: given w/o carbidopa, caution in renal failure, avoid in narrow angle glaucoma
Patient counseling: avoid protein meals, pyridoxine, MAY WEAR OFF between doses, give W/ FOOD, DECREASE NA intake
Monitor: dyskinesias, and ADR
Carbidopa
- 2% becomes 10% absorption in brain if combined with Levodopa.
- Given with Carbidopa
- AVOID high protein meals
CLASS: Dopamine Agonist
MOA: inhibit decarboxylation of levodopa in GI/peripheral tissues
USES: combined with levodopa to increase therapeutic effects, lowers levodopa doses
D/R: PO
ADR: none
DINT: increases beneficial effects of levodopa
CONTRA: should be given with levodopa
PC: avoid high protein meals, eat consistent amount of protein, might WEAR off
MONITOR: dyskinesias, and ADR
Pramipexole
- “Pecs…pramiPEXole” –> so you don’t work out legs –> restless leg syndrome –> always wants to work out (compulsive behavior), so gets daytime sleepiness
- Movements are more steady
- Screen children, alcohol abusers, novelty seekers, gamblers, and binge eaters.
- Compulsive behavior show up after 9 months from starting.
CLASS: Nonergot dopamine receptor agonist
MOA: Binds to dopamine D2 and D3 receptors, activating dopamine receptors, mildly blocks serotonergic and alpha-adrenergic receptros
USES: Monotherapy, movement performance improved, motor fluctuations, with levo for RLS,
D/R: PO
ADR: CONSTIPATION, IMPULSIVE CONTROL (ex: gambling, binge eating, novelty seeking), n/v, dizziness,
DINT: Cimetidine
CONTRA: Compulsive behaviors
PC: Several weeks to see maximum effects
MONITOR: Screen for impulsive control (gambling, binge eating, novelty seeking)
Entacapone
- Put a “cap” on levodopa
- Improve symptoms
- STABLIZES Levodopa
- ADR yellow -orange discolored urine
CLASS: Catechol-O-methyltransferase (COMT) inhibitor
MOA: Selectively inhibits enzyme COMT, resulting in decreased metabolism of levodopa GI/peripheral tissues
USES: INCREASES half-life of levodopa, PREVENT “wearing off” of levodopa
DOSE: PO 200mg each dose of lev/carb
ADR: yellow-orange discolored urine, increased levodopa levels may lead to dyskinesias, orthostatic hypotension. GI problems (vomiting, diarrhea)
DINT: increases drug levels of COMT
CONTRA: Give in combo with levodopa
PC: importance of levodopa/carbidopa
MONITOR: adverse effects
Selegiline
- Adverse reaction Hypertensive Crisis.
- Avoid giving after noon to prevent insomnia
- NO TYRAMINE (aged cheese, deli meat, sausage, soy sauce, aged meat, packed fish, tofu, sauerkraut, beer)
- WITH Breakfast and Lunch ONLY (sounds like “LINGUINE” – so pasta that you like to eat for breakfast and lunch BUT no aged cheese or meats.
- If you eat your pasta with tyramine youll get HTN CRISIS.
CLASS: MAO-B Inhibitor
MOA: Selectively and irreversibly inhibits MAOB inhibitor enzyme that inactivates dopamine
USES: improves motor function, prolong effects of levodopa
D/R: Tabs and capsules WITH breakfast and lunch
ADR: Hypertensive crisis, buccal mucosa irritation
DINT: Tyramine (aged cheese, deli meat, sausage, soy sauce, aged meat, packed fish, tofu, sauerkraut, beer)
CONTRA: Meperidine, SSRIs
PC: last dose before noon to avoid insomnia, avoid foods containing tyramine
MONITOR: BP, kidney function, older patients
Alzheimer’s Meds
Donepezil
Memantine
Donepezil
- elderly could faint/dizziness
- increase slowly after 1-3 months
- Caution with Heart and Respiratory Problems
- Sick sinus syndrome (arrhythmia), Bronchoconstriction, bradycardia, Asthma, COPD (monitor airway)
Class: cholinesterase inhibitor
MOA: inhibit breakdown of acetylcholine by acetylcholinesterase, increases acetylcholine at synapses
USES: mild –> severe AD
DOSE: PO, ODT, titrate slowly
ADR: most serious - brochoconstriction, bradycardia, sick sinus syndrome (most dangerous)
INT: first gen antihistamines, tricyclic antidepressants, conventional psychotics
CONTRA: asthma, COPD, Liver disease, heart disease,
Counseling: not cure AD but slow progression, risk of ADR with high doses
Monitor: titrate carefully go slow
Memantine
- prevents toxic levels of Ca from blocking memory formation
- keep on 3 months
- can be added with donepezil
- NOT beneficial for MILD AD
- can also have HTN crisis
- can get bronchospasms
Class: NMDA receptor antagonist
MOA: regulates Ca uptake into cells, prevent toxic levels
USES: moderate –> severe AD
DOSE: PO
ADR: dizziness, HA, confusion, constipation, diarrhea, HTN, hypotension (in ER - extended release)
INT: other NMDA antagonists, sodium bicarbonate
CONTRA: drugs that alkanilize urine, renal or hepatic impairment
Counseling: improved symptoms
Monitor: BUN and Creatinine
Antiepileptic seizures
phenytoin phenobarbital carbamazepine Valproic Acid (Depakote) Gabapentin Levetiracetam
- ALL mainly CONTAIN*
- screen for: suicide risks, BUN, Creatinine
Phenytoin
phenyt-O-in “O” as in ORAL –> ADR (gingival hyperplasia), DrugINT (ORAL contraceptives, anything that goes in the mouth like CNS depressant drugs, and ALCOHOL), Counseling (take 0.5 g of folic acid in the ORAL, good ORAL hygiene)
On a bell curve– (10-20) therapeutic range
short dose = short 1/2 life
long dose = long 1/2 life
Class: AED
MOA: blocking sodium into neurons to decrease activity produced seizures
USES: Partial/general TC seizures
DOSE: PO
ADR: gingival hyperplasia, measles like rash,
INT: ORAL contraceptives, CNS depressants, alcohol
CONTRA: HLA-B genes (ASIAN descent), Pregnancy Category D
Counseling: good ORAL hygiene, 0.5mg folic acid daily, avoid alcohol and CNS depressing drugs
Monitor: suicide risks, LFTs, excessive drug levels.
Phenobarbital
“phen-O-BARB-ital…”
- O is the same as phen-O-toin (oral contra. interaction).
- 8 yr old Barb talk too much asking for more alcohol (addiction) ‘gaba gaba gaba gimme gimme gimme’… shes very hyper (PARADOXICAL)
- We don’t wanna kick Barb out or else she’ll die alone (respiratory depression)
- So we need to slowly get her sober (dont stop med abruptly)
- Can cause addiction
Class: Anticonvulsant barbiturate
MOA: Binds to GABA receptors, leading to receptors to respond to GABA more….GABA GABA GABA
USES: Partial/General TC seizures, IV form can treat status epilepticus, sedation and sleep.
DOSE: IV, IM, PO
ADR: Lethargy Depression, learning impairment, agitation, confusion in elderly, dependence, PARADOXICAL response in children, intermittent porphyria
INT: ORAL contraceptives, warfarin, CNS depressants, alcohol,
CONTRA: hx of intermittent poryphyria, suicidal tendencies, pregnancy risk D
Counseling: can cause ADDICTION, limit alcohol, dont stop abruptly, weeks to reach therapeutic levels
Monitor: CNS depression, ataxia, nystagmus, BUN, Creatinine, LFTs
Carbamazepine
“CARB-amazepine”
- Grapefruit juice has CARBS (avoid cause we tryna get abs)
- Larger dose taken @ bedtime
- Take with meals…“carbs”
- ADR: Bone marrow suppression & photo sensitivity
- ADR lessen after couple of weeks
Class: Traditional AED
MOA: suppress high frequency neuronal discharge
USES: Partial and TC seizures, NOT ABSENCE seizures, symptomatic control for bipolar disorders, trigeminal and glossopharyngeal neuralgia
DOSE: LARGER dose @ BEDTIME, take WITH MEALS
ADR: decrease after couple of weeks, SJS, CNS (nystagmus, blurred vision, diplopia, ataxia, vertigo, unsteadiness, headache) Blood/fluid (leukopenia, anemia, thrombocytopenia, hypo-osmolarity, rash,
INT: GRAPEFRUIT juice, ORAL contraceptives, warfarin, phenytoin, phenobarbital,
CONTRA: Pregnancy risk D, HLA-B (asian gene)
Counseling: ADR decrease after few weeks, LARGE DOSE at bedtime, avoid grapefruit juice, WITH MEALS
Monitor: suicide LFTs, CBC, BMP
Valproic Acid (Depakote)
- for Increased ammonia levels
- DON’T CHEW “ACID”
- IV to PO ASAP (can come with extended release)
- all kinds of seizures
Class: Trad AED
MOA: Suppress high frequency neurons targeting sodium channels, prevent calcium form entering, enhance GABA
USES: Seizure disorders, bipolar disorder, migraines
DOSE: PO, start low go slow
ADR: GI (n/v, indigestion, hepatoxicity, pancreatitis, hyperammonemia) rash, weight gain, hair loss, tremor, blood dyscrasia, well tolerated
INT: epileptic drugs, topiramate, , carbapenem antibiotics, avoid, meropenem and imipenem
CONTRA: Preg Risk D, avoid combo w/ other drugs children under 2 years of age with a preexisting liver dysfunction.
Counseling: WITH FOOD, S&S of liver failure and pancreatitis, birth control, women of childbearing age, take with folic acid, don’t chew or crush
Monitor: suicide, LFT, lipase, amylase, therapeutic effects, switch IV to PO ASAP
Gabapentin
“GAB-a-PEN-t-IN”
- Gabby got a pen in her foot, so she needs Gabapentin for the tingling (neuropathy)
- Can take a nap with the ADR (somnolence, dizziness, fatigue)
Class: Newer AED
MOA: May enhance GABA release – UNKNOWN
USES: FDA approved mostly given for nerve pain rather than AED, especially neuropathy (nerve tingling or damage)
DOSE: PO, 3 divided doses
ADR: Somnolence, dizziness, ataxia, fatigue, nystagmus, peripheral edema
INT: No known
CONTRA: Preg Risk C, caution with breast feeding,
Counseling: diminish with longer use, avoid driving.
Monitor: suicide, BUN, Creatinine
Levetiracetam
- Given for seizures
- Europe has this drug faster
- Used a fair amount in hospitals
Class: Newer AED
MOA: Unknown
USES: FDA approved, adjunctive therapy for myoclonic, primary gen TC seizures.
Off label use: migraine, bipolar disorder, pediatric epilepsy, approved in Europe for partial seizures.
DOSE: PO, reduce dose if renal impairment
ADR: drowsiness, weakness, suicidal ideation
INT: None
CONTRA: dose reduced with renal impairment, avoid breast feeding since Pregnancy Risk C
Counseling: about ADR
Monitor: suicide risk BUN, Creatinine
