EMERGING THERAPEUTIC PROFILES

Question 1

Which receptors does cannabis act on ?

What class drug is Cannabis?

Answer 1

• CB1 and CB2
• Class B

Question 2

What does cannabis induce?

Answer 2

-psychotic like episodes
- hallucinations if taken at a young age when the brain is still developing

Question 3

What is the link between Cannabis & Chronic pain

Answer 3

Cannabis has been found to alleviate chronic pain.
There is debate over its use for chronic pain as there is a high risk for the user in developing dependancy if it is used for a long period of time.

• but its efficacy and safety is proven if used acutely.

Question 4

What is the link between Cannabis & Vommiting

Answer 4

Cannabis has been found to been effective in reducing emesis.

• Emesis/vomiting can be caused by taking toxic drugs as a means of removing them = acts on NTS (vomiting centre) to reverse peristalsis
• Contracts diaphragm to push stomach down and prevent vomiting
• Cannabis shown to be effective in chemotherapy induced nausea-vomiting = more effective than some conventional anti-emetics
• However, there are side effect and continued use can induce nausea/vomiting

Question 5

Cannabis in treating Neurological problems

Answer 5

• Can be used in treatment for MS, epilepsy and Huntington’s chorea
• Its efficacy depends on the type of epilepsy = doesn’t induce dependency
• Some papers will say it is effective, but others say it isn’t = all conclude that it is effective depending on the subjective belief that it will work (could be placebo)

(d) Increase appetite in HIV patients = get the munchies
(e) PTSD

Question 6

• Explain the mode of action of cocaine.
  -What class of drug is cocaine
• What are the effects of cocaine

Answer 6

-Cocaine is a blocker of DAT, SERT and NET. It results in an increase in dopamine, seratonin and noradrenaline.

• It is class A drug
• Cocaine has anxiety, Inc. heart rate, High BP and depression.

Question 7

What is the use of cocaine

Answer 7

• Nasal surgery: causes vasoconstriction by the release of noradrenaline
• Dental surgery: blocks voltage gated Na channels - blocks pain and used in dental surgery as a topical anaesthetic

Question 8

How does Ketamine work?
What is it used for?, what are its effects physiologically?

Answer 8

 NMDA receptor blocker
 Predominantly used as an anaesthetic (horse tranquilizer) because
- Doesn’t supress breathing
- Stimulates the circulatory system which is important as traumatic shock increases risk of hypotension
 Can overdose on ketamine and it can induce hallucinations and psychosis = only happens in adults and not in kids
 Categorised as a class C drug
 Can also induce anxiety, panic, increased heart rate and raised blood pressure
 Bind to NMDA receptor (ion channel) = receptor is an important glutamate excitatory receptor involved in memory which is why psychosis is induced
 Can be abused as a drug of choice

Question 9

Describe the use of ketamine for treatment resistant depression

Answer 9

(a) Treatment-resistant depression
- Given at a much lower dose than that used to induce analgesia
- Has rapid onset (within 2 hours)
- Important experiment done on a severely depressed population (who were sectioned) = SSRIs and other medication had been unsuccessful
- Compared electroconvulsive therapy with repeated doses of ketamine = ketamine was more effective

Question 10

Ketamine for chronic pain

Answer 10

(b) Pain
- Has good potential for treating chronic pain = by blocking pain transmission
- Need to solve problems of toxicity in long term use

Question 11

What is the mode of action of Amphetamine?
What is their effects

Answer 11

 increases the release of monoamines = too much dopamine release can lead to psychotic effects
 Eventual DAT/SERT/NET reversal
 Categorised as a class B drug
 Induces anxiety, panic, paranoia, delusion, increased heart rate and raised blood pressure
 Shown to have a larger harm to self than others

Question 12

what are the medical indications of Amphetamines

Answer 12

(a) ADHD
- Dopamine is involved in inducing concentration so increasing this = increases concentration
- Abnormal brain structure/function can be resolved upon chronic amphetamine administration
- Relatively safe at the dose prescribed
(b) Anti-depressant
- SSRIs, TCAs, SNRI, MAOIs
(c) Stroke
- Amphetamine increases noradrenaline in the synapse
- Also sued to boost cancer patient morale
- Can be used for narcolepsy as it is a psychostimulants and narcoleptics do not get addicted to amphetamines (as they have low orexin = involved in addiction)

Question 13

What is the mode of action of MDMA?
What is their effects

Answer 13

leads to eventual DAT, NET reversal
class A drug
 Induces anxiety, panic, paranoia, delusions, increased heart rate and raised blood pressure

Question 14

what are the medical indications of MDMA

Answer 14

1. PTSD:

• MDMA administered twice (8hr psychotherapy session)
• Improvements still apparent 6 years post treatment

2. Anti depressant:
   - Ecstasy increases serotonin levels
    Ecstasy also increases oxytocin in the brain

Question 15

what are the medical indications of psilocybin?
(magic mushroom)

Answer 15

 Could help treat people with severe depression
 Trials of psilocybin blocked by drugs law red tape, says David Nutt