1.) Rate is determined by lipophilicity. High lipid solubility = rapid absorption from the gastrointestinal tract and good distribution of the drug to the brain. 

2.) Redistribution refers to when high lipid soluble drugs are distributed to organs with high blood flow such as the brain, heart and kidneys. This increases the duration of action of the drug.

3.) Metabolism of BD's:

•  Dealkylation of active metabolites
• Oxidation catalyzed by the Cytochrome P450 isozymes. 
• Conjugation of oxidized metabolite to form glucuronides that are excreted in the urine. 

4.) Diazepam, Chlorazepate, Chlordiazepoxide, Prazepam and Ketazolam.  They all undergo the 3 steps of biotransformation and prolong the duration of action. 

5.) Oxazepam, Lorazepam, Temazepam and Lormetazepam.

Can be used in patients who have a low Cytochrome P450 activity and can be used in neonates, the elderly and patients who suffer from Liver Cirrhosis. 

6.) Enzyme induction refers to an increase in the metabolic activity of a drug. 

Barbiturates (Phenobarbital, Thiopental, etc) are known for this effect.

An increase in the rate of metabolism will cause a decrease in the therapeutic effect of the drug