When it comes to controlled and targeted delivery of medication to the body, essentially three main aspects need to be taken into consideration: the delivery method, the timings, and possible interferences.
Medicinal drugs are designed to be taken at a fixed dose at a fixed time, so as to keep the concentration of the drug in the body at an ideal level. If the concentration goes too low then there will not be enough to produce the desired therapeutic effect. If the concentration goes too high then the drug will start to cause adverse effects. Depending on the method of delivery the time taken between the administration of the drug and its response will vary.
There are various delivery methods of drugs, ranging from common methods such injections or tablets to less common methods such as absorption through skin or mucosa, each having their own advantages and disadvantages. The choice of delivery method depends on the individual patient and drug that is being administered. The desired effect and site of activity also dictates which method is best used, for example if a drug needs to be fast acting or if prolonged action is required.
There are many potential interferences with medication: food and drink, other medications (including over-the-counter ones), patient-specific interactions can all effect how a medicinal drug works in a particular instance for a particular person. There may be reasons attributable to our genetics that some interactions occur, such as those that cause allergic reactions. Drug interferences can alter the way our bodies absorb and process medications. However, not all interactions are bad and some can improve drug effectiveness so it is important to understand the effects any interactions may have on the working of a drug and consequently on the body.
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