Pharmacology

Question 1

Components of pain

Answer 1

Affective
Cognitive
Discriminative
Arousal
Motor

Question 2

Pain transmission horns

Answer 2

Non-noxious stimuli (dynamic allodynia) through A beta - Laminae 3 4 5 deep horns

Nociceptive mechanical and thermoceptive stimuli (polymodal, static allodynia) through A delta - Laminae 1 2o 5 superficial horns and some deep

Nociceptive mechanical, thermoceptive, and chemical stimuli (polymodal) through C - Laminae 1 2o superficial horns

Question 3

Wide dynamic range horn

Answer 3

Horn 5

Question 4

Serotonin excitatory and inhibitory receptors

Answer 4

5-HT1 = inhibitory

5-HT3 = excitatory

Question 5

AMPA

Answer 5

More selective to sodium entry than calcium and the antagonist is CNQX (cyan quaxaline)

Question 6

NMDA

Answer 6

repeated depolarisation is needed as well as two ligands (glu + gly), and the antagonists are ketamine (also used to treat depression) and memantine but neither are used any more clinically due to serious side-effects such as hallucinations and motor effects

There are presynaptic receptors but less studies on them, all we know is that the repeated depolarisation mechanism for releasing magnesium is not important for them

Question 7

SP and NK-1

Answer 7

SP: co-released with NKA, CGRP, and glutamate

IP3: GPCR, postsynaptic, increases release of calcium from intracellular stores by generating IP3, antagonists have failed, involved in mood, stress, anxiety, and pain

Question 8

Descending controls transmitter systems

Answer 8

Opioidergic, noradrenergic, and serotonergic

Question 9

Morphine microinjection provides analgesia in which section?

Answer 9

PAG

Question 10

What drugs cause schizophrenic attacks and susceptible patients?

Answer 10

LSD and phencyclidine

Question 11

What receptor causes the psychedelic effects of LSD?

Answer 11

5HT2A

Question 12

Which receptors does LSD not affect?

Answer 12

5HT3 5HT4

Question 13

How does the immune system promote addiction?

Answer 13

TLR4

Question 14

Tinazidine Contraindications

Answer 14

Should not be taken with fluvoxamine (antidepressant) or ciprofloxacin (antibiotic) either. If it is taken in high doses for a long time, it causes withdrawal effects.

Question 15

Local Anaesthetic Nerve Fibre Order Of Action

Answer 15

L.As block in the following order: small myelinated axons (Ad), then unmyelinated axons (C- fibres), then large myelinated axons (Ab) & motor axons.

Question 16

What does PABA inhibit?

Answer 16

Sulphonamide

Question 17

Drug-induced PD

Answer 17

Drugs that reduce the amount of dopamine in the
brain (e.g. reserpine).

Drugs that block dopamine receptors (e.g.
antipsychotics such as chlorpromazine).

Question 18

Which anti-epileptic drugs are highly bound to plasma proteins?

Answer 18

phenytoin & valproic acid

Question 19

What is the status of activity of antiepileptic drug metabolites?

Answer 19

they are active and also cleared through hepatic pathways, some of the older anti-epileptics are hepatic microsomal enzyme potentiators

Question 20

Valproate special use

Answer 20

In adolescents where grand & petit mal co-exist since it is effective against both (unlike most antiepileptics)

Question 21

Which drug is the first choice in absence seizures?

Answer 21

Ethosuximide (T subtype inhibited as it is the one responsible for absence seizures)

Question 22

Tiagabine and vigabatrin MOA

Answer 22

Tiagabine GAT1 inhibited reuptake

Vigabatrin GABA-T inhibited transaminase inactivation

Question 23

Uses of vigabatrin

Answer 23

Adjunct therapy in refractory complex partial seizures

West’s syndrome (infantile spasms)

Question 24

Which BZD is also an anti-depressant?

Answer 24

Alprazolam

Question 25

What is midazolam also used for?

Answer 25

Anaesthesia

Question 26

Which hypnotic reduces REM sleep the least?

Answer 26

Zolpidem (and BZDs relatively less), GH release is unaffected, SW reduced

Question 27

BZD duration of action

Answer 27

Diazepam: long acting for anxiolysis Flurazepam: long acting for hypnosis Temazepam: intermediate acting for hypnosis Triazolam - short acting

Question 28

Which BZD has an active metabolite?

Answer 28

Nordazepam -> N-desmethyldiazepam (60 hour half-life)

Question 29

What is special about buspirone?

Answer 29

Takes long time to work (cannot be given for acute attack) and can be withdrawn abruptly and safely

Question 30

3Zs side effects

Answer 30

Zolpidem & zaleplon: nightmares, agitation, headache, G.I upset, dizziness Zopiclone: taste alteration, impairment of driving skills, palpitations (following withdrawal from drug after prolonged use) Zolpidem & zopiclone: anterograde amnesia (more so than zaleplon)

Question 31

Which hypnotic causes endocrine changes and what are they?

Answer 31

Ramelteon, increase in prolactin and decrease in testosterone

Question 32

What is the danger in using tacrine?

Answer 32

Tacrine causes hepatotoxicity (liver damage/failure) too. Thus, it is required simultaneous monitoring for hepatotoxicity, recently not used much.

Question 33

Which AChE and BuChE inhibitor affects the heart?

Answer 33

Galantamine (also nAChRs enhancer) | Do not forget that memantine can also cause hypertension is a side-effect

Question 34

Which drug, if given in gradual doses, does not show as much side-effects?

Answer 34

Rivastigmine

Question 35

Which drug is given in gradual doses to avoid toxicity?

Answer 35

Carabamezepine

Question 36

Other Treatments For AD

Answer 36

Levetiracetam: An anticonvulsant with a novel mechanism of action (which is not clear), anti-inflammatory processes in the brain, may slowdown the AD progression. Caprylidene (Caprylic triglyceride): A formulation of coconut oil, which release ketones, provide alternative energy source to glucose. It might be useful in mild to moderate AD to improve memory and cognitive function, but it does not reverse neuronal degeneration. Curcumin (Extract of turmeric): It has both the anti-inflammatory and anti-oxidant properties that can suppress the formation of NFTS and Aβ deposit. Latrepirdine (Dimebon): It is a weak inhibitor of AChE, BuChE, and NMDA receptors. Methylthioninium chloride compound (MTC): It is a tau kinase inhibitor that reduce the formation of NFTs.

Question 37

Partition Co-efficient

Answer 37

(P = [organic]/[aqueous]).

Question 38

Examples of pharmacological approaches to bypassing the blood brain barrier

Answer 38

Chemical delivery system (lipidisation): enhanced delivery of ganciclovir to the bran by covalently attaching with 1-methyl-1,4-dihydronicotinate to a hydroxymethyl group. Prodrug: Valacyclovir is a prodrug of acyclovir. In oral administration it rapidly gets converted to acyclovir. Polymeric micelles: Pluronic P85 micelles loaded with a neuroleptic drug is targeted to the brain by conjugating micelles with neurospecific antibodies as targeting moieties. Nanoparticles (ApoE-albumin): hexapeptide dalargin

Question 39

Why are CGRP antagonists not used?

Answer 39

Hepatotoxic