1. Factors affecting the absorption and distribution of sedative hypnotics

The lipophilicity of the drug affects the rate of absorption which in turn affects its distribution. The more lipid soluble a drug is, the more likely it is to cross the bbb and more likely to have a rapid set of action and thus suppress the CNS

2. What is meant by redistribution?

This happens when drugs get absorbed into the systematic circulation and is distributed from the brain to other tissue. Most lipid soluble are distributed to the brain, heart, kidney etc and then it gets distributed to the fat and muscle. This process prolongs the duration of action of the drug.

3. BD metabolised

• Dealkylation to active metabolites
• Oxidation by cyp P450 to active metabolite
• Conjugation of the oxidised metabolite with glucuronic acid to form an inactive metabolite.

4. BD converted to desmethyldiazepam include diazepam, cholarazepam, prazepam, chlorodiazepoxide, ketazolam. Acitve metabolites gives us a longer duration of action.

5. Oxazepam, lorazepam, temazepam, lormetazepam. This helps with patients who have liver cirhosssis , patients who on cimetidine or sort and therefore help as it does not depend on the enzyme to produce an effect.

6. This is when a drug increases the amount of enzymes in the body and thus increase the rate of metabolism and thus results in a lesser therapeutic effect.