Nervous System Pharm II Flashcards
What meds are used to treat epilepsy?
i. Diazepam (also psychiatric)
ii. Phenytoin
iii. Lamotrigine
iv. Topiramate
v. Valproate
What is the primary action of Phenytoin?
Modulates neuronal voltage-dependent sodium and calcium channels
What are the indications of Phenytoin?
Control of generalized tonic-clonic and complex partial seizures
What are the AEs of Phenytoin?
i. Hepatotoxicity
ii. Pancytopenia
iii. Dizziness
iv. N/V
v. Megaloblastic anemia
What is the black box warning for Phenytoin?
Severe hypotension and cardiac arrhythmias with injectable form
What are the CIs for Phenytoin?
Abrupt withdrawal
What interacts with Phenytoin that is important to know?
Very long list
CYP3A4 Inducers
Do blood levels need to be moinitored in pts on Phenytoin?
Yes
What nutrients need to be supplemented with Phenytoin?
Vitamin D, B2, B6, B12, folic acid
What is the primary action of Lamotrigine?
Inhibition of voltage-dependent sodium channels, decreasing presynaptic glutamate and aspartate release
What are the indications of Lamotrigine?
Bipolar I
Epilepsy
What are some of the AEs of Lamotrigine?
Nausea
Insomnia
SI
Headache
Depression, anxiety
Speech and vision disturbance
What is the black box warning for Lamotrigine?
Serious rashes included Stevens-Johnson Syndrome
What are the CIs for Lamotrigine?
Abrupt Withdrawal
What interacts with Lamotrigine that is important to know?
Progestins
OCPs
Hypericum perforatum
What is the primary action of Topiramate?
Carbonic anhydrase inhibitor
What are the indications of Topiramate?
Generalized tonic-clonic, partial, Lennox-Gastaut seizures
What are some of the AEs of Topiramate?
Metabolic acidosis
Nephrolithiasis
Osteoporosis
Hypokalemia
Glaucoma
Mood disturbance
Many more
What are the CIs for Topiramate?
Avoid abrupt withdrawal
What interacts with Topiramate?
Alcohol
OCPs
Metformin
What is the primary action of Valproate?
Increases GABA effects
What are the indications of Valproate?
Partial and absence seizures
What are the AEs of Valproate?
Many
encephalopathy
Headache
Tremor
N/V
Diarrhea
What is the black box warning for Valproate?
Hepatotoxic
Pancreatitis
Teratogenic
What are the CIs for Valproate?
LV Disease
Mitochondrial disorders
Pregnancy
What are other uses of Valproate that you should know?
Migriane Prophylaxix
Bipolar disorder
What is the protype anti-Parinsonism drug?
Levodopa and carbidopa
What other drugs also have anti-Parkinsonism effects?
Amantadine
How does levodopa work as an anti-Parkinsonism drug?
It’s decarboxylated to dopamine in the brain, improves motor, neurological and altered mood sxs of Parkinson’s dx
How does carbidopa work as an anti-Parkinsonism drug?
It works by decreasing the peripheral breakdown of levodopa by dopamine carboxylase
What are the AEs of Levodopa and Carbidopa?
Anorexia
NV via stimulation of the emetic center
Depression
Mood changes and anxiety
Long term : hallucinations, dyskinesia
What anti-Parkinson’s drug is also used to treat restless leg syndrome?
Pramipexole
What are some of the AEs of Pramipexole?
Hypotension
Extrapyramidal symptoms
Rhabdomyolysis
Hallucinatioins
HA
What is the primary action of Benztropine?
Antagonizes acetylcholine and histamine receptors
What are the indications of Benztropine?
Parkinsonsim
Extrapyramidal sx
What are some of the AEs of Benztropine?
Tachycardia
Dry mouth
Urinary retention
Edema
Sedation
What are some of the CIs for Benztropine?
Use in children <3 yo
Glaucoma
BPH
Tardive dyskinesia
What interacts with Benztropine?
Other acetylcholine inhibitors
What are some of the indications for Bromocriptine?
Hyperprolactinemia
Acromegaly
Parkinson’s dx
What is the primary action of Bromocriptine?
Selective dopamine agonist in the pituitary
What are the AEs of Bromocriptine?
GI upset : N/V
Dizziness, HA
Hallucinations
Nasal congestion
Involuntary movements
What do you not what to do if using bromocriptine to treat Parkinson’s disease?
Abrupt discontinuation
What are the CIs for using Modafinil?
In what condition would it be dangerous to use atropine?
Acute closed angle glaucoma
What drug is used to treat cholinesterase inhibitor poisoning? How?
Atopine
It acts as a parasympatholytic or muscarinic antagonist drug and will help decrease the increased levels of Ach in the body
What are some of the AEs of sympathomimetic drugs?
i. CV : Tachycardia, palpitations, arrhythmias, HTN
ii. CNS : tremors, HA, restelessness, insomnia, appetite suppressioin
iii. Urinary : retention of urine, difficult or painful urination
What is the primary action of Carbamazepine?
Anticonvulsant
What are the indications of Carbamazepine?
Epilepsy, trigeminal neuralgia
What are the AEs of Carbamazepine?
Fatigue
Dizziness
Headache
Nausea
Aplastic Anemia
What is the black box warning of Carbamazepine?
Serious Dermatologic Rxns
HLA-B*1502 Allele and Aplastic anemia/Agranulocytosis
CI for Carbamazepine
Bone marrow suppression
MAO inhibitor use within 14 days
What interacts with Carbamazepine?
Phenelzine and others
Amantadine
Mechanism:
1. Antagonizes excitatory N-Methyl-D-Aspartate (NMDA) receptors to down regulate the glutamate system
2. Increases release of dopamine
3. Anticholinergic Effects
Uses: treat levodopa-induced dyskinesias late in the disease as well as influenza-A (rarely)
S/E: may exacerbate mental illness in patients with psychiatric illness or substance abuse problems; insomnia, dizziness, hallucinations, agitation, orthostatic hypotension, peripheral edema, dyspepsia; neuroleptic malignant syndrome
Pregnancy category C
Scopolamine
Mechanism: Belladonna alkaloid that blocks cholinergic transmission from the vestibular nuclei to higher CNS centers
Uses: certain types of muscle problems (e.g., some Parkinson-like conditions, certain muscle spasm problems) and certain stomach or intestinal problems (e.g., irritable colon syndrome), preventing nausea and vomiting associated with motion sickness
Has a transdermal formulation
Pregnancy category C
Classes and Drugs to treat Alzheimer’s Disease
Indirect Cholinergic Agonists (AchE Inhibitors)
Donepezil
Rivastigmine
NMDA glutamate receptor antagonist
Memantine
Donepezil and Rivastigmine
Mechanism: increase acetylcholine activity in the CNS by inhibiting acetylcholinesterase (AchE) as acetylcholine contributes to cognition and memory.
Uses: for symptom control only in mild-moderate disease
- Dementia associated with Parkinson’s disease (rivastigmine)
- Mild-severe Alzheimer’s (donepezil)
Pregnancy category c (donepezil)/category B (rivastigmine)
Memantine
Mechanism: Acts on the glutamatergic system by blocking NMDA-type glutamate receptors
Uses: moderate to severe Alzheimer’s disease and Lewy Body Dementia
Usually given with AchE Inhibitor
S/E: confusion, dizziness, drowsiness, HA, insomnia, agitation, hallucationations, vomiting, anxiety, hypertonia, cystitis, increased libido
Pregnancy category B
Drugs and classes to treat Multiple Sclerosis
Reduce neuronal inflammation
Fingolimod
Glatiramer acetate
Interferon beta 1
Reduce muscle spasticity
Baclofen
Botulinum toxin
Tizanidine
Interferon beta 1
Mechanism: Immunomodulatory. alters the expression and response to surface antigens and can enhance immune cell activities; how it works in MS is unknown
Uses: relapsing forms of MS
Warnings: hyper/hypothyroidism, bone marrow suppression, flu-like symptoms, severe hepatic injury, severe injection site injury, neuropsychiatric manifestations, thrombotic microangiopathy
IM formulation only
Pregnancy category C
Glatiramer Acetate
L-Glutamic acid polymer with l-alanine, l-lysine, and l-tyrosine and acetate
Mechanism: unknown, studies suggest it activates glatiramer-specific Treg cells that migrate into the CNS and down-regulate inflammation to myelin antigens in the periphery
Uses: Relapsing-remitting Multiple Sclerosis
Warnings: hypersensitivity reactions, immediate post-injection reactions, chest pain, lipoatrophy and skin necrosis, “interference with useful immune function”
IM formulation only
Pregnancy category B
Fingolimod
Sphingosine 1-Phosphate (S1P) Receptor Modulator
Mechanism: blocks the lymphocytes’ ability to emerge from lymph nodes; therefore, the amount of lymphocytes available to the central nervous system is decreased, which reduces central inflammation
Uses: Multiple Sclerosis, relapsing forms
CI: MI, unstable angina, stroke, transient ischemic attack, decompensated heart failure requiring hospitalization, or New York Heart Association (NYHA) class III/IV heart failure in the past 6 months; Mobitz Type II second- or third-degree atrioventricular (AV) block or sick sinus syndrome (unless patient has a functioning pacemaker); baseline QTc interval ≥500 msec; concurrent use of a class Ia or III antiarrhythmic
SE: headache, nausea, diarrhea, abdominal pain, increased liver enzymes, flu, back pain, cough, sinusitis, hypertension, AV block, depression, dizziness, migraine, increased triglycerides, bronchitis, HSV
PO formulation
Pregnancy category C
Botulinum Toxin
MoA: acetylcholine release inhibitor
Treats : upper/lower limb spasticity
Baclofen
MoA unknown
Uses: spasticity of MS, spinal cord injury, rheumatic disorders. NOT indicated for stroke, cerebral palsy, and Parkinson’s disease has not been established and, therefore, it is not recommended for these conditions
TAPER off if discontinuing (hallucinations/seizures)
SE: drowsiness, asthenia, dizziness, headache, nausea
Pregnancy category C
Tizanidine
Alpha-2-adrenergic agonist (centrally acting); presumably reduces spasticity by increasing presynaptic inhibition of motor neurons
SE: hypotension, sedation, risk of liver injury, hallucinations, interactions with CYP1A2 inhibitors (ciprofloxacin)
Pregnancy category C
Classes and Drugs of Anticonvulsants
Na-channel inhibitors
Carbamazapine
Phenytoin
GABA-analogues
Gabapentin
Pregabalin
Others
Valproate
Topiramate
Lamotrigine (Psych lecture)
Alprazolam (Psych lecture)
Diazepam (Psych lecture)
