Route of Administration
Importance of Choice of Route of Administration
The choice of route of administration is very
important because it directly affects how well and how fast a drug works in the
body. Selecting the proper route ensures that the drug reaches its target
site safely and effectively, with minimal side effects. The choice depends
on several factors related to the drug, patient, and desired
action.
1. To Achieve Desired Effect
Different routes give different speeds and durations of drug
action.
- For immediate
effect, routes like intravenous (IV) or inhalation are
used.
- For slow
and prolonged effect, oral or transdermal routes are
preferred.
Thus, the route helps to control onset, intensity, and duration of the drug’s action.
2. To Ensure Proper Drug Absorption
Some drugs are destroyed by stomach acid or digestive
enzymes and cannot be given orally (e.g., insulin). Such drugs are given by injection
or inhalation.
Choosing the correct route ensures the drug is absorbed properly and remains
effective.
3. To Avoid First-Pass Metabolism
When drugs are taken orally, they pass through the liver
before reaching the bloodstream, which can reduce their effectiveness. Routes
like sublingual, buccal, rectal, or parenteral
avoid this effect and increase bioavailability.
4. To Improve Patient Comfort and Compliance
The selected route should be convenient and acceptable
for the patient.
- Oral
route is easy and painless, preferred for most patients.
- Injections
are avoided when possible because they are painful and need trained
personnel.
Choosing a comfortable route ensures patients follow their treatment properly.
5. To Suit the Patient’s Condition
Some routes are chosen based on the patient’s health
condition.
- Unconscious
or vomiting patients cannot take oral drugs — rectal or injectable
routes are used.
- Infants
or elderly may require liquid or topical forms.
Hence, the patient’s age, condition, and ability to swallow play an important role.
6. To Reduce Side Effects and Toxicity
Local routes (like topical, ocular, or nasal)
deliver drugs directly to the affected area, reducing systemic side effects and
minimizing toxicity.
7. To Ensure Accurate Dose Delivery
Parenteral routes like IV or IM are preferred when precise
dose control is needed, especially in emergencies or hospital settings.