Question

Short answer questions: Please type your answers.

1. Using one drug class as an example (opioids), discuss the relationship between the duration of drug effects, the speed of onset of drug action and the addiction potential of that drug.

AND

2. Describe 5 ways that a drug can increase neurotransmission at the synapse. You do not need to give specific drug examples, but rather, indicate the general mechanisms by which agonism can occur.

Answer 1

Morphine :

Morphine is an opioid agonist. It works on specific areas of CNS as a stmulant or depressant. It is used mainly as a analgesic, sedative.

Its duration of action is 3-6 hours.

Its speed of onset is 15-60 mins.

Morphine is a narcotic opioid. It have a high degree of potential for dependency. Morphine abusers take morphine in grams. Morphine produced pronounced mental and physical dependence. It have a high abuse rate.

2. Neurotransmission can be increased by drugs through one of the following mechanism:

- increasing the release of neurotransmitter like dopamine

- by increased generation of action potentials

- by altering the postsynaptic receptors. They either block or activate the receptor site.

- altering the removal of neurotransmitter from synapse.

- altering the enzymes activity on the neurotransmitters.