Neurology Flashcards
Which drugs is used to treat Myasthenia Gravis?
Pyrodostigmine
How is Guillian Barre treated?
IV immunoglobulin
What is the treatment for migraines?
Simple analgesia: Paracetamol, Aspirin, NSAIDs
Triptans: Sumatriptan
+/- antiemetic: domperidone, metoclopramide
What drugs are used for migraine prophylaxis?
Beta blockers: propranolol
Tricyclic antidepressants: Amitriptyline, Dosulepin, Nortriptline
Anti-epilepsy drugs: Topiramate, Sodium Valproate
What drugs are given after an ischaemic stroke?
Thrombolysis with rTPA i.e. alteplase (intravenously)
Antiplatelets - aspirin 300mg (given immediately unless alteplase has been started)
if aspirin is not tolerated give clopidogril
What route is alteplase administered?
Intravenously
What drug is given if aspirin is not tolerated?
Clopidogrel
What is the treatment for SAH?
Nimodipine
Fluids
What type of drug is Nimodipine? (MOA)
Calcium channel blocker
Blocks L type calcium channels, therefore prevents Ca entry into the cells
Myocardial and smooth muscle contractility is depressed – these drugs mainly affect smooth muscle.
Dilate coronary blood vessels and reduce afterload
Nimodipine does not lower heart rate (heart rate may increase)
Which drugs are used for focal epilepsy?
Carbamazepine
Levetiracetam
Lamotrigine
Remember: CLL
Which drugs are used for generalised epilepsy?
Valproate
Lamotrigine
Levetiracetam
Remember: VLL
What is the mechanism of action of Carbamazepine?
Voltage gated Na+ channel blocker on pre-synaptic membrane
Blocks the Na+ influx; reduces neuronal excitability and decreases the action potential
What are the side effects of carbamazepine?
Dizziness Dry mouth Ataxia Fatigue Headache Diplopia Blurred vision Hyponatraemia Stevens-Johnson’s syndrome (rarely <0.01%)
What are the important pharmacokinetics of carbamazepine?
Enzyme inducer of cytochrome P450; induces metabolism of itself
Interactions with other anti-convulsants
Grapefruit can significantly increase serum levels of this drug - avoid grapefruit
What is the mechanism of action of valproate?
Weak sodium ion channel blocker
Inhibitor of GABA degrading enzymes
(Increased GABA stops action potential)
What are the side effects of valproate?
Nausea Diarrhoea Gastric irritation Weight gain Hyponatraemia
What other drugs (other than CLL or VLL) are used for epilepsy?
Phenytoin
Gabapentin
What is the mechanism of action of phenytoin?
Acts as a voltage-gated Na+ channel blocker on the pre-synaptic neuronal membrane
Limits action potential transmission
Hence limiting spread of seizure activity
What are the side effects of phenytoin?
Insomnia Headache Rash Constipation Vomiting Gingival hyperplasia Liver damage
What is the mechanism of action of lamotrigine?
Inhibits voltage-gated Na+ channels and/or Ca2+ channels
Acts on pre-synaptic neuronal membrane
Reduces action potential and excitatory signals
What are the side effects of lamotrigine?
Nausea Vomiting Diarrhoea Tremor Insomnia Blurred vision Aggression
What is the mechanism of action of levetiracetam?
SV2A is a synaptic vesicle protein required for neurotransmitter release
Levetiracetam blocks this and reduces neurotransmitter release
Induces an anti-epileptic effect
What are the side effects of levetiracetam?
Headache Fatigue Anxiety Irritability Drowsiness Constipation
What is the mechanism of action of both gabapentin and pregabalin?
Voltage-gated Ca2+ channel antagonist
What are the 4 drug classes in Parkinson’s Disease?
L-Dopa
Dopamine agonists
MAO-B inhibitors
COMT inhibitors
What is the mechanism of action of L-dopa
L-Dopa is taken up by the dopaminergic neurones and decarboxylated to become dopamine within the presynaptic terminals
What is l-dopa prescribed with?
a dopa-decarboxylase inhibitor e.g. carbidopa
What does carbidopa do?
It stops l-dopa being metabolised peripherally so more can go to the brain
It also prevents the peripheral side effects of dopamine (nausea and vomiting)
What is the combination of l-dopa and carbidopa called?
Sinemet
What are the PERIPHERAL and CENTRAL side effects of L-dopa?
CENTRAL: confusion and hallicunations
PERIPHERAL: nausea, vomiting
Give 2 examples of dopamine agonists
Ropinirole
Pramipexole
Apomorphine
What is the mechanism of action of dopamine agonists?
Act directly on the post synaptic dopamine receptors (D2)
What are the side effects of dopamine agonists?
Dopaminergic side effects, somnolence and impulse control disorders (hyper sexuality/pathological gambling)
Give 2 examples of monoamine oxidase inhibitors?
Selegiline
Rasagiline
What is the mechanism of action of Selegiline?
Selegiline inhibits monoamine oxidase, which would break down dopamine, therefore allowing dopamine to act for longer
Give 2 examples of COMT inhibitors?
Entacapone
Tolcapone
What is the mechanism of action of Entacapone?
COMT inhibitor
Inhibiting Catechol-o-methyltransferase results in longer L-dopa half-life and duration of action
What types of drugs are alteplase and tenectaplase?
Recombinant Tissue Plasminogen Activator (rtPA)
thrombolytics
What is the MOA of alteplase?
Recombinant form of tissue plasminogen activator
Catalyses conversion of plasminogen to plasmin
Promotes fibrin clot lysis
What are the indications of alteplase?
Acute ischaemic stroke within 4.5 hours of onset
Myocardial infarction within 12 hours of onset
Massive pulmonary embolism
What are 2 treatment options for relapsing remitting MS?
Adelimumab
Dimethyl fumarate
What is the aim of treatment in primary progressive MS?
Symptom control
