If you are prescribed medication for the first time, it is only permitted to issue you with a
15 day supply. This is a legally enforced scheme to prevent waste, as a new drug may not be effective or have adverse effects. You would then be prescribed alternative medication and the first drug would no longer be used.
In addition to this "15-day scheme" there is further legislation for the supply of medicines. Most medication can be supplied for up to 3 months. There are some exceptions. The contraceptive pill may be supplied for up to 6 months; sleeping pills and tranquilizers for up to 1 month. In consultation with your doctor, a shorter period can be prescribed. You would then only be issued with medication for this shorter period.
Personnel who are not exempt from prescription charges, will be required to pay for the initial issue, but not for the supply over the 15 day period. However, prescription charges will apply if alternative medication is prescribed.