Antiepileptic, Anti parkinsonism, Antidementia agents

Question 1

MOA of antiepileptics

Answer 1

1. Intentional reduction of excitatory neurotransmitter release
   a) reduction of axial conductivity by delaying Na + influx-through fast Na + channels
   b) * Inhibition of Ca2 + influx through presynaptic channels in thalamic neurons
   c) effect on the operation of SV2A
2. Enhancement of inhibitory system activity by facilitating GABA-mediated hyperpolarization to reduce excessive neuronal activity
3. Inhibition of glutamate activation
   (AMPA receptor blockade or NMDA receptor blockade)-with the aim of reducing excessive neuronal activity

Question 2

MOA of antiepileptics

Answer 2

1. Intentional reduction of excitatory neurotransmitter release
   a) reduction of axial conductivity by delaying Na + influx-through fast Na + channels
   b) * Inhibition of Ca2 + influx through presynaptic channels in thalamic neurons
   c) effect on the operation of SV2A
2. Enhancement of inhibitory system activity by facilitating GABA-mediated hyperpolarization to reduce excessive neuronal activity
3. Inhibition of glutamate activation
   (AMPA receptor blockade or NMDA receptor blockade)-with the aim of reducing excessive neuronal activity

Question 3

Valproic Acid

Answer 3

Blockade of voltage-dependent Na + and Ca2 + channels in neurons,
inhibits GABA transaminase (prolongs GABA activity).

anticonvulsant effect (control of epilepsy), mood stabilization
Generalized (TC, A) and focal epilepsy
Status epilepticus
Bipolar disorder

SE: Teratogenic activity
NB! Take special care with women of childbearing potential

Question 4

Ethosuximide

Answer 4

anticonvulsant effect (control of epilepsy)

Blockade of Ca2 + channels in neurons

Generalized epilepsy (A)

Question 5

Lamotrigine

Answer 5

Blockade of voltage-dependent Na + and Ca2 + channels in neurons,
anticonvulsant activity (control of epilepsy), mood stabilization 

Generalized (TK, A) and focal epilepsy
Bipolar disorder

Question 6

Carbamazapine

Answer 6

Blockage of voltage-dependent Na + channels in neurons,
anticonvulsant activity (control of epilepsy), mood stabilization,
co-analgic effect

Generalized (TK) and focal epilepsy
Bipolar disorder
Neuropathic pain (trigeminal neuralgia)

Question 7

Valproic Acid

Answer 7

Blockade of voltage-dependent Na + and Ca2 + channels in neurons,
inhibits GABA transaminase (prolongs GABA activity).

anticonvulsant effect (control of epilepsy), mood stabilization
Generalized (TC, A) and focal epilepsy
Status epilepticus
Bipolar disorder

SE: Teratogenic activity
NB! Take special care with women of childbearing potential

Question 8

Ethosuximide

Answer 8

anticonvulsant effect (control of epilepsy)

Blockade of Ca2 + channels in neurons

Generalized epilepsy (A)

Question 9

Lamotrigine

Answer 9

Blockade of voltage-dependent Na + and Ca2 + channels in neurons,
anticonvulsant activity (control of epilepsy), mood stabilization 

Generalized (TK, A) and focal epilepsy
Bipolar disorder

Question 10

Carbamazapine

Answer 10

Blockage of voltage-dependent Na + channels in neurons,
anticonvulsant activity (control of epilepsy), mood stabilization,
co-analgic effect

Generalized (TK) and focal epilepsy
Bipolar disorder
Neuropathic pain (trigeminal neuralgia)

Question 11

Gabapentine

Answer 11

Structural analogue of GABA

Inhibition of voltage-sensitive Ca2 + channels,
anticonvulsant effect (control of epilepsy), coanalgesic effect

Focal epilepsy
Neuropathic pain (diabetic neuropathy, postherpetic neuralgia)
Chronic pain syndrome

Question 12

Levetiracetam

Answer 12

Binds to the synaptic vesicle protein 2A(SV2A)
Affects the neurotransmitter
exocytosis

Generalized (TC) and focal epilepsy
Status epilepticus

Question 13

Topiramate

Answer 13

1) Blocks * Kainate/ AMPA(amino hydroxymethylisoxazole-propionic acid) receptors
2) blocks voltage dependentNa + channels
3) blocks Ca2 + channels
4) GABA-A receptorallosteric modulation
Generalized and focal epilepsy

Question 14

Anti parkinsons agents MOA

Answer 14

.Drugs that produce symptomatic relief in PD act by

1) elevating regional dopamine levels (levodopa, MAOBIs, COMT inhibitors)
2) stimulating dopamine receptors (DA agonists), 3)inhibiting the effect of cholinergic afferents (anticholinergics),
4) inhibiting glutaminergic NMDA receptors (amantadine).

Question 15

• L-DOPA + Decarboxylase Inhibitors (DCI)

Answer 15

CNS ~ 10%By converting L-dopa to dopamine in the nigrostriatal tract,restores neurotransmission in Corpus striatumeliminates EPS

Parkinson’s disease
Parkinsonism (except one caused by antipsychotics)

Question 16

Carbidopa, benserazide

Answer 16

peripheral levodopa inhibitors of metabolism(DCI does not cross the blood-brain barrier)Reduces dopamine-induced gastrointestinal side effects - nausea, vomiting and cardiovascular side effects - arrhythmias and hypotension

Parkinson’s disease
Parkinsonism (except one caused by antipsychotics)

Question 17

Non-selective agonists of striatal dopamine D2 receptor

Answer 17

Pramipexole
Bromocriptine
NB! Dopaminergic control of prolactin secretion in the tuberoinfundibular tract

Question 18

COMT inhibitors

Answer 18

Entacapone (does not cross BBB)
Tolcapone (Crosses BBB)

Parkinson’s disease
* Hyperprolactinemia (bromocriptine only)

Question 19

Cholinolytic agents

Answer 19

Dopamine acts as an ACh antagonist in certain regions of the CNS.
In the event of dopamine deficiency in the nigrostriatal tract,
ACh is one of the neurotransmitters that mediate EPS

Trihexifenidil

As a central actiong M1 choline blocker blocks Ach-induced EPS

Parkinsonisms
Correction of EPT induced by antipsychotic agents

Question 20

Acetylcholinesterase inhibitors

Answer 20

Donepezil

• Rivastigmine (also inhibition of * butyrylcholinesterase)
  Reduces symptoms of neurodegeneration, slows cognitive decline

SE: cholinergic hyperactivation
IA: Medicines with anticholinergic properties
(1st generation histamine receptor blockers, tricyclic antidepressants)

Alzheimer’s dementia
Vascular dementia
Parkinson’s dementia (additional indication for rivastigmine)

Question 21

Glutamate NMDA receptor channel blocker

Answer 21

(uncompetitive NMDA receptor antagonist)

Memantine

Alzheimer’s dementia