Opioids

Question 1

What are the 3 opiates?

Answer 1

Codeine, morphine and thebaine.

Question 2

What is an opioid?

Answer 2

A natural or synthetic exogenous drug that mimics morphine.

Question 3

What is the only semi-synthetic exogenous opioid?

Answer 3

Heroin.

Question 4

What are the synthetic exogenous opioids?

Answer 4

Methadone and fentonyl.

Question 5

What are the endogenous opioids?

Answer 5

Enkephalins and endorphins.

Question 6

What are the semisynthetic narcotics that contain morphine?

Answer 6

Heroin and hydromorphone.

Question 7

What are the semisynthetic narcotics that contain thebaine?

Answer 7

Oxycodone and etorphine.

Question 8

What are some totally synthetic narcotics?

Answer 8

Pentazocine, meperidine, fentanyl, methadone, LAAM and propoxyphene.

Question 9

What is the difference between an opioid and an opiate?

Answer 9

Opioids are any drug that mimics morphine, opiates are non-synthetic opioids.

Question 10

How do you make heroin?

Answer 10

1. Grow a papaver somniferum (sleep-inducing poppy)
2. Wait until the flowers’ petals fall
3. Slit the egg-shaped seed pod
4. Collect the milky sap - crude opium!
5. It thickens and darkens
6. Boil it in lime, organic detritus sinks
7. This leaves a white top layer of morphine, which can be modified to create heroin.

Question 11

Approximately what percentage (by weight) of opium is morphine (McKim, 2003)?

Answer 11

10%

Question 12

Approximately what percentage (by weight) of opium is codeine (McKim, 2003)?

Answer 12

0.5%

Question 13

The pharmacological effects of morphine and heroin are essentially identical because…

Answer 13

Heroin is converted into morphine in the brain.

Question 14

When is heroin more potent than morphine?

Answer 14

When injected - the acetyl groups in the molecule make it more lipid soluble and it gets to the brain faster.

Question 15

Water molecule charge movement causes HOH to ionize, becoming…

Answer 15

H+ OH-

Question 16

Where morphine has an two OHs (hydroxyls), heroin has…

Answer 16

CH3COO - acetyl/ethyls

Question 17

Why does fat solubility increase heroin’s potency?

Answer 17

Because blood-brain barrier has a bilayered phospholipid membrane which is impenetrable to ionised molecules (morphine), but not for non-ionised molecules (heroin).

Question 18

What do exogenous opioids do in the CNS?

Answer 18

They hijack the endogenous system (for endorphins etc.), affecting mu, kappa and delta receptors.

Question 19

What is nociception?

Answer 19

Pain perception.

Question 20

What is the pre-thalamic destination of nociception?

Answer 20

The dorsal horn of the spine. Then goes to the thalamus.

Question 21

What is the cortical destination of nociception?

Answer 21

The somatosensory cortex.

Question 22

What is the path for peripheral to central sensation for vision?

Answer 22

Optic chiasm, LGN (thalamus), visual cortex.

Question 23

What is the path for peripheral to central sensation for audition?

Answer 23

Cochlear nucleus and inferior colliculus, medial geniculate nucleus (thalamus), auditory cortex.

Question 24

How do opioids affect the nociception pathway?

Answer 24

Fibres from the periaqueductal grey (midbrain) descend onto the dorsal horn and turn down nociception sensitivity.

Question 25

Where has evidence of opium use been found?

Answer 25

- Ceramic bowls in Brittany - Paleobotanical evidence from Neolithic sites in Southern Spain (4200 BC) - The Odyssey - mixed with wine by Helen to cheer up Telemachus. - Galen prescribed it - Paracelsus referred to it in 1520.

Question 26

Who popularised Laudanum use in Britain?

Answer 26

Thomas Sydenham (1924-1689), mixed with wine.

Question 27

Who isolated morphine, and when?

Answer 27

German pharmacist Friedrich Sertuerner in 1803. Named it after morpheus, Greek god of dreams.

Question 28

Who isolated codeine?

Answer 28

French chemist Pierre Robiquet in 1821.

Question 29

What is codeine also known as?

Answer 29

Methoxymorphine.

Question 30

Why are over the counter pain drugs containing morphine illegal in some countries, such as Greece?

Answer 30

Because of how addictive they are.

Question 31

Who produced diacetylmorphine?

Answer 31

English chemist C R Alder Wright in 1874. Cooked with acetic acid. Also discovered by Hoffman and Dresser in 1898.

Question 32

What is diacetylmorphine?

Answer 32

Heroin.

Question 33

What company produced heroin, and when and why did they stop?

Answer 33

Bayer. In 1913 when it became apparent that it was in fact addictive.

Question 34

What did Siegel et al (1982) do?

Answer 34

Divided rats into 3 groups - similarly tested, differently tested and control only - and gave them injections of heroin (dextrose for control only) in either the same or a different room to the test injection.

Question 35

What did Siegel et al (1982) find?

Answer 35

Mortality rates were 32%, 64% and 96% respectively. Therefore: slow does increase before test improves prospects, showing that some tolerance/adaptation occurs. Also, some of these are psychological - the environment is the CS which signals heroin.

Question 36

What did Siegel (1978) do?

Answer 36

3 groups of rats again, two boxes, morphine and saline. Temperature first increased in response to morphine then developed tolerance. When sal-room condition given morphine in the room they usually had saline, they became hyperthermic - environment.

Question 37

What bodily systems do opiates primarily affect?

Answer 37

The intestines and the CNS.

Question 38

What follows an acute effect?

Answer 38

An opposing effect.

Question 39

The initial effect of analgesia is followed by...

Answer 39

Pain

Question 40

The subsequent effect of yawning is preceded by...

Answer 40

Respiratory depression

Question 41

Opiate-induced euphoria is followed by...

Answer 41

Dysphoria

Question 42

The acute effects of opiates include lowered BP and pupil constriction, which is later followed by...

Answer 42

Increased BP and pupil dilation

Question 43

Flushed, warm skin immediately after taking opioids is followed by...

Answer 43

Goosebumps.

Question 44

What is the term for pupil constriction?

Answer 44

Miosis

Question 45

What is the term for pupil dilation?

Answer 45

Mydriasis

Question 46

What changes in terms of the net effect of morphine after many injections?

Answer 46

The initial effect remains the same, but the opponent effect starts sooner and counteracts it, meaning that the net effect is a lower initial spike.

Question 47

What happens to the effect graph of taking a larger dose of morphine having developed tolerance to a lower dose?

Answer 47

Although the opponent effect starts earlier, the net effect spike is as high as a normal dose without tolerance.

Question 48

What hedonic assumption do theories of action-outcome learning (Thorndike, 1911) make?

Answer 48

Actions that obtain favourable outcomes are more likely to be repeated.

Question 49

According to action-outcome learning, when might drug-related actions become more likely to re-occur?

Answer 49

When taken during opposing effect - e.g. dysphoria is -100, drug increases to +100 is a very large hedonic change.

Question 50

What type of receptors does methodone affect?

Answer 50

It's a mu-receptor agonist.

Question 51

How is methodone usually taken?

Answer 51

Orally

Question 52

How does methodone work in relieving heroin addiction?

Answer 52

It reduces craving, and thus relapse, whilst not giving extreme effects.

Question 53

What are the long-term effects of methodone?

Answer 53

No organ damage, patient capable of working, but does produce problems with libido and excessive sweating.