To achieve the maximum response to medicines and prevent any abuses, discipline should be maintained in their control, administration and storage. Consider all medicines to be dangerous. Many become potentially toxic if the recommended levels of treatment are exceeded or if they are given in the wrong way.

Some medicines have a very narrow range between treatment levels and poisoning. A good example is monensin, 100g/tonne is the therapeutic level and 300g is toxic.

Light and heat destroy medicines and freezing also has an adverse effect, particularly on vaccines.