Download D 3 Analgesics answer key

D 3 Analgesics
1. State what is meant by the term analgesic. Explain the difference in the mode
of action of mild and strong analgesics?
a substance that reduces pain;
mild analgesics intercept pain at the source/interfere with production of
substances that cause pain;
strong analgesics bond to receptor sites in the brain/prevent the transmission
of pain impulses;
2.State the general names of the two functional groups attached to the benzene ring in a
molecule of aspirin?
carboxylic (acid)/alkanoic (acid); ester;
3.The use of aspirin can have beneficial effects for the user, but can also produce some
unwanted side effects. State one beneficial effect (other than its analgesic action) and one
unwanted side effect.?
used to treat mini-strokes;
prevents heart attacks/reduces risk of heart attack/thins the blood/
anti-coagulant;
relieves symptoms of rheumatological diseases/anti-inflammatory;
reduces fever;
4.Explain what is meant by developing tolerance towards codeine and state why this is
dangerous?
increasing amounts needed to produce same effect;
increasing amounts cause damage/death;
5.Identify two functional groups present in the structure of aspirin?
carboxylic (acid)/alkanoic (acid); ester;
6.Explain the advantages and disadvantages of using morphine and its derivatives as a
strong analgesics?
a.
In the relief of severe pain caused by injury, chronic disease such as cancer, prior to and
recovery from surgery; in the treatment of diarrhoea by producing a constipating effect; to relieve
coughing by suppressing the ‘cough centre’ situated in the brain stem. Disadvantages: Opiates
produce drowsiness, mood changes and mental clouding (psychological effects). Users develop
tolerance to the drug (need more for the same effect), as well as physical dependence, a state in
which users do not function properly without a drug. Withdrawal is experienced when the drug is
not regularly administered; symptoms include restlessness, sweating, fever, chills, vomiting,
increased rate of respiration, cramping, diarrhoea, unbearable aches and pains..
7..Name
the
nitrogen
containing
functional
group
in
acetaminophen?
Amine,alcohol,ketone
8.Suggest how heroine can chemically be prepared from morphine?
in the acetylation of morphine to yield heroin (diacetylmorphine) the phenolic OH group on the 3carbon is the first to react to give, as an intermediate, 3-O-monoacetylmorphine, which is further
acetylated to heroin. Similarly, when heroin is deacetylated, either by hydrolysis or enzymatically, the
more reactive 3-acetyl group tends to be removed first to yield 6-O-monoacetylmorphine as the
predominant intermediate, although low levels of 3-O-monoacetylmorphine may also be formed under
these condition