The presence of a benzene ring, a hydrocarbon chain, a steroid nucleus or halogen (-Br, -CI, -F) groups favours lipid solubility. Water solubility is favoured by the possession of alcoholic (-OH), amide {-CO.NH,} or Car boxy lie (-COOH) groups, and the formation of glucuronide and sulphate conjugates.

It is useful to classify drugs in a physicochemical sense into:

• Those that are variably ionised according to environmental pH (electrolytes) (lipid-soluble or water-soluble)

• Those that are incapable of becoming ionised whatever the environmental pH (un-ionised, nonpolar substances) (lipid-soluble)

• Those that are permanently ionised whatever the environmental pH (ionised, polar substances) (water-soluble).

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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