NEUROLOGICAL DRUGS

Question 1

what is levodopa?

Answer 1

dopamine precursor

Question 2

how can levodopa act centrally on the brain?

Answer 2

crosses blood brain barrier

Question 3

where in the brain does levodopa replaces the deficit in dopamine?

Answer 3

basal ganglia

Question 4

give an ophthalmological contraindication of levodopa

Answer 4

closed angle glaucoma as levodopa can cause further increase in intraocular pressure

Question 5

what kind of parkinsonism contraindicates use of levodopa

Answer 5

drug induced

Question 6

give a circulatory side effect of levodopa

Answer 6

Postural Hypotension, syncope and drowsiness

Question 7

what can occur to the urine of a patient taking levodopa?

Answer 7

discolouration

Question 8

why shouldn’t levodopa be used with anaesthetics?

Answer 8

increases the risk of dysrhythmias

Question 9

why shouldn’t levodopa be used with MAOI antidepressants?

Answer 9

increase the risk of hypertension

Question 10

what type of drug is phenytoin?

Answer 10

anti-convulsant

Question 11

how does phenytoin work?

Answer 11

block voltage gated sodium channels which prevents influx of sodium and prevents action potential formation for a seizure. Prevent the spread of neuronal excitability and therefore inhibits seizure activity spread

Question 12

which seizures is phenytoin not active against?

Answer 12

absent

Question 13

apart from epilepsy, give a condition that phenytoin is used to treat

Answer 13

trigeminal neuralgia

Question 14

what is the metabolism of phenytoin?

Answer 14

cytochrome p450

also induces p450

Question 15

what type of drug is carbamazepine?

Answer 15

anti-convulsant

Question 16

how does carbamazepine work?

Answer 16

increases release of GABA which inhibits the CNS by blocking sodium channels - stops action potential

Question 17

What is carbamazepine 1st line treatment for?

Answer 17

Generalised tonic clonic seizure
Focal seizures
Trigeminal neuralgia= Controls the pain, reduces the frequency and severity of the attacks

Question 18

carbamazepine is contraindicated in what abnormality that causes immune depression?

Answer 18

bone marrow depression

Question 19

carbamazepine is contraindicated in what heart abnormality?

Answer 19

AV node conduction abnormality

Question 20

carbamazepine and sodium valproate are contraindicated in which disease?

Answer 20

acute porphyria ( metabolic disorders)

Question 21

use of carbamazepine can lead to which organ insufficiencies?

Answer 21

renal

hepatic

Question 22

give 2 blood disorders that can be caused by carbamazepine

Answer 22

agranulocytosis

thrombocytopenia

Question 23

how does carbamazepine interact with cytochrome p450?

Answer 23

Metabolised and induced by it

Question 24

what type of drug is sodium valproate?

Answer 24

anti-convulsant

Question 25

how does sodium valproate work? (3 things)

Answer 25

increase GABA by preventing re-uptake Blocks sodium channels Decreases plasma conc of aspartate (excitatory neurotransmitter)

Question 26

If a patient is taking sodium valproate and has a) renal impairment b) hepatic impariment what should be the recommendation?

Answer 26

a) reduce the dose | b) stop taking sodium valproate

Question 27

give 3 other side effects of sodium valproate

Answer 27

weight gain sedation hair loss

Question 28

why shouldn't sodium valproate be given with neuroleptics?

Answer 28

decrease effect

Question 29

why shouldn't sodium valproate be given with TCAs?

Answer 29

reduce effect

Question 30

what type of drug is lamotrigine?

Answer 30

anti-convulsant

Question 31

Except for epilepsy and seizures, give 2 instances when lamotrigine can be used

Answer 31

lennox-gastaut syndrome | Depression in Bipolar disorder

Question 32

what type of drug is levitaracetam?

Answer 32

anti-convulsant

Question 33

how does levitaracetam work?

Answer 33

selectively prevents epileptic burst firing and propagation of seizures without affecting normal neuronal activity

Question 34

aside from a tablet, how can levitaracetam be given?

Answer 34

injection

Question 35

why should caution be taken when stopping a patient on levitaracetam?

Answer 35

withdrawal seizures

Question 36

give 4 side effects of levitaracetam

Answer 36

Abdo pain Anorexia co-ordination difficulties sedation/fatigue

Question 37

why should levitaracetam be given with caution in pregnancy

Answer 37

can be difficult to maintain seizure control when pregnant

Question 38

Why should the use of L-dopa be used with caution in patients with cardiovascular disease?

Answer 38

Due to the risk of hypotension

Question 39

What is the risk of using L-dopa in elderly patients or patients with existing cognitive or psychiatric disease?

Answer 39

This is due to the further risk of confusion and hallucinations

Question 40

What physiological affect does L-dopa have?

Answer 40

Can cause confusion and hallucinations

Question 41

What is a long term complication of using L-dopa?

Answer 41

Increase wearing off effect which causes the notion off the on-off symptoms of parkinsons

Question 42

What common GI symptoms do you get with L-dopa

Answer 42

Nausea and vomiting

Question 43

What affect can L-dopa have on a person weight?

Answer 43

Can cause anorexia

Question 44

What is the side effect of giving L-dopa to frequently or to high of a dose?

Answer 44

Dyskinesia --> involuntary movement

Question 45

What drug is given in conjunction with L-dopa and why?

Answer 45

Carbidopa = Peripheral dopa-decarboxylase inhibitor to prevent the conversion to dopamine outside of the brain

Question 46

Why should you not give L-dopa with antihypertensives?

Answer 46

Due to the risk of further hypotension

Question 47

When is phenytoin used for status epilepticus?

Answer 47

When BZDP does not work

Question 48

Is phenytoin the first line treatment for generalised and focal seizures?

Answer 48

No it's not as other anticonvulsants have less side effects and interactions

Question 49

What is the consequence of phenytoin having a low therapeutic index?

Answer 49

The chance of phenytoin toxicity is high as missing a dose or taking to much can have severe effects

Question 50

Why shouldn't pregnant ladies take phenytoin?

Answer 50

Fetal Hyuntain syndrome = abnormal cranialfacial features and lower IQ

Question 51

What should patients take before conception when on phenytoin or Carbamazepine?

Answer 51

High dose of folic acid

Question 52

What does long term use of phentyoin do to the skin?

Answer 52

Cause coarse skin, acne and gum hypertrophy

Question 53

What are the dose related neurological effects of phentyoin?

Answer 53

Cerebellar toxicity ( ataxia, nystagmus and discoordination) and impaired cognition and consciousness

Question 54

How does phentyoin cause osteomalacia and haematological disorders

Answer 54

It induces vitamin d and folic acid metabolism

Question 55

What happens in hypersensitivity reaction of phentyoin or Carbamazepine?

Answer 55

From mild rash to life threatening rare antiepileptic hypersensitivity syndrome

Question 56

Phenytoin toxicity caused by overdose can cause death by what mechanism?

Answer 56

Respiratory depression and cardiovascular collapse

Question 57

What drugs effect the efficacy of phenytoin, carbamazepine, levetiracetam and sodium valproate?

Answer 57

``` Drugs that reduce the seizure threshold such as SSRI's TCA antidepressants Tramadol Antipsychotics ```

Question 58

What happens in life threatening antiepileptic hypersensitivity syndrome?

Answer 58

Clinical features include severe skin reactions , fever and lymphadenopathy with systemic (e.g. haematological, hepatic, renal) involvement and mortality of about 10%.

Question 59

Carbamazepine is used as a alternative treatment of what two conditions?

Answer 59

Prophylaxis of Bipolar disorder ( lithium uneffective) | Chronic neurogenic pain

Question 60

What are the potential consequence of carbamazepine exposure in utero?

Answer 60

Neural tube defect, cardiac and urinary abnormalities and cleft palate

Question 61

What are common side effects of carbamazepine?

Answer 61

Nausea and vomiting | Ataxia and dizziness

Question 62

What type of seizures is sodium valproate first line choice for?

Answer 62

Generalised seizures and absence seizures

Question 63

Except for seizures what else is sodium valproate used for?

Answer 63

Migraine | Bipolar disorder for acute treatment of manic episodes or prevention of relapse

Question 64

Which anti epileptic drug has the greatest risk of fetal abnormality?

Answer 64

Sodium valproate

Question 65

At what points in pregnancy should sodium valproate definitely be avoided?

Answer 65

Contraception and first trimester

Question 66

What is the potential fetal abnormalities caused by sodium valproate?

Answer 66

Neural tube defect Craniofacial, cardiac and limb abnormalities Developmental delay

Question 67

What affect does sodium valproate have on cytochrome p450?

Answer 67

inhibitor

Question 68

What is Lennox-Gastaut Syndrome ?

Answer 68

It is type of epilepsy with many different types of seizures

Question 69

What are the two main types of seizures in which lamotrigine is used for?

Answer 69

Monotherapy and adjuvant therapy for generalised seizure and focal seizure

Question 70

What condition can be exacerbated by lamotrigine?

Answer 70

Parkinsons

Question 71

What two drugs decrease plasma conc of lamotrigine?

Answer 71

Oestrogen and rifmapicin

Question 72

What drug increases plasma conc of lamotrigine?

Answer 72

Sodium Valproate

Question 73

What is the interaction between levetiracetam and methotrexate?

Answer 73

Increases the plasma conc of methotrexate

Question 74

What fibres does phentyoin have affect on that causess the antiarrhythmic and cardiotoxic effects?

Answer 74

cardiac Purkinje fibres