Taking multiple drugs or herbal supplements at the same time
without proper medical advice despite of their actual need is
called as Polypharmacy.
It is important to consider a patient's polypharmacy when
obtaining patient history or chief complaint due to following
factors:
- To determine/prevent any drug interactions:
Taking multiple drugs or herbal supplements at the same time can
lead to unintended drug interactions For example: antagonism
(Glucagon-Insulin, Hydrochlorothiazide + Traimterene etc),
synergism (Tyramine + Monoamine oxidase inhibitors, Acetylcholine +
Physostigmine), additive effect (Aspirin + paracetamol, Amlodipine
+ atenolol)
- To identify any potential iatrogenic diseases:
Polypharmacy can be the underlying cause (iatrogenic effects) for
the chief complaint and taking history of medications will help in
ascertaining the diagnosis. For example, antipsychotics such as
Haloperidol can induce Parkinsonism, Angiotensin Converting Enzyme
inhibitors cause cough, Gentamicin can result in nephrotoxicity,
High ceiling diuretics can result in Hypokalemia etc
- To eliminate adverse effects: Polypharmacy can
lead to serious adverse effects, by taking a thorough history of
medications will help in differentiating adverse effects from
clinical manifestations of a disease
- To prevent failure of drug regimen:
Polypharmacy can lead to unintended reactions (tachyphylaxis,
tolerance, idiosyncrasy) which can result in patient non compliance
and failure of the current therapy.
- To plan optimized clinical course for current
condition: By taking a thorough history of patient's
polypharmacy, a physician can plan the drug regimen such that there
is no repetition of the drugs, drug interaction or unwanted drug
effects. There by it helps in planning the clinical course of
treatment.
- To improve patient compliance: A patient's
polypharmacy can help to know the knowledge and the degree of
compliance of the patient towards therapy. Hence, further actions
can be planned to achieve patient compliance.