Route of drug administration is the path that is used to deliver drugs into the body to treat, cure or prevent the occurrence of disease. As the name indicates route means paths so basically route of drug administration is the route or path which is followed by the drug to reach its site of action.
Selection of suitable Route of drug administration plays an important role for patient health because the onset of drug action and bioavailability of the drug is greatly dependent on the drug route and the route may be selected on the following basis,
Ease Of the Patient/Age of patient
Nature of the drug
Patient Condition
Required Onset of action
Pharmacokinetics & Pharmacodynamics
Ease Of Patient/Age of patient
Ease of the patient means which route is comfortable for the patient. For example, the oral route is not suitable for those patients who have difficulty in swallowing.
Nature of the drug
Selection of drug route administration is also dependent on the nature of drugs, this mean nature of some drugs is such that those can only be administered by a specific route like insulin.
Patient Condition
The selection of drug route administration is also dependent on the condition of the patient.
If Patient is suffering from nausea and vomiting. The oral route is not recommended.
Required Onset Of Action
The selection of the route of drug administration is also dependent on the drug onset of action.
For example,if delayed release action is required then it can be administered in the controlled release tablet by oral route.
Classification Of Drug Routes
The action of a drug may be required locally on a specific site or it can be used for systemic effect. Based on the above-mentioned requirement there are two main factors for the classification of drug routes,
Local effect
Systemic Effect
Following are main routes for drug administration,
Enteral Route
Parenteral Route
Topical
Transdermal
Inhalation
Enteral Route
The enteral route of administration is the type of drug administration route in which the drug is administered to the body through GIT.
We can use both ends of GIT for the enteral route meaning the drug may be administered through the mouth or by rectal route as well.
Enteral Route is further divided into following,
Oral(Per Oral), PO
Sublingual
Rectal Route
Oral Route Of Administration
The oral route of administration is one of the most commonly used routes for drug administration and in this route drugs are in the form of a tablet, capsule, pills, syrup or suspension and are taken by mouth.
Benefits of Oral Route
Following are some major benefits or advantages of the oral route,
Oral administration is cheapest route
Patient Acceptance is high
Easy to administer
Safe to use
No device is required to administer
Disadvantages Of Oral Route
Following are some drawbacks of the oral route
Not suitable for patients suffering from nausea and vomiting.
Not suitable for unconscious patients.
Bioavailability is low due to the first-pass effect.
Food may interact with drugs.
Objectionable, due to bitter taste.
Sublingual Route/Buccal Route
The sublingual route is the route of drug administration in which the drug is placed below the tongue or in between gums and gingiva.
In the sublingual or buccal route, the drug is absorbed through the mucosa into the circulation.
The sublingual route provides fast dissolution of drugs.
The first pass effect is prevented.
Not suitable for bitter drugs.
Nitroglycerine is a common example of a drug administered through this route.
Rectal Route
The rectal route is also an important route for drug administration and is used for local and systemic effects.
In the rectal route, drugs are absorbed through the rectal mucosa.
This route can be used for unconscious patients.
The drugs which are irritating to the stomach can be administered through this route.
Suppositories and enemas are dosage forms that are administered through this route.
The patients suffering from nausea and vomiting are good candidates for this route.
Parenteral Route
Parenteral is derived from the Greek word "para" which means beside and "enteral" means intestine so the parenteral definition is as follow,
Drug administration other than GIT.
Or
The parenteral route or parenteral meaning is the route of drug administration other than intestine,it is also known as injection route.
Bioavailability through the parenteral route is highest because through this route the first-pass effect is bypassed.
The fastest onset of drug action is achieved through this route because usually in the case of the IV route drug is directly administered into the blood circulation.
Types Of Parenteral Route
The parenteral route is further divided into the following,
Intravenous Route (IV)
Intramuscular Route (IM)
Subcutaneous Route (SC)
Intravenous Route (IV)
In the IV route drug is directly administered into the veins. This route provides rapid drug action and can be used in emergency conditions.
Intramuscular Route (IM)
In this route, drugs are injected into the muscles of the body.
Subcutaneous Route (SC)
It is the route in which drugs are injected below the skin.
Above mentioned are three most commonly used parenteral routes, other parenteral routes which are not widely used are as follow,
Intraspinal Route
Intrathecal Route
Intra-Arterial Route (IA)
Intraperitoneal Route (IP)
Intracardiac Route
Intracerebroventricular
Topical Route
The topical route is the route in which drugs are applied to the skin surface mucous membrane or into body cavities like the ear, nose, eyes etc
Topical route is further subdivided into the following,
Epidermic Route
In the epidermal route, a drug is applied to the skin by rubbing into the skin.
Enepedermic Route
In this route,drugs are applied to outer skin surfaces in the form of creams or ointments etc.
Insufflation
In this route the drug in finely divided powders are applied to the body cavities.
Irrigation
In irrigation, the cavities of the vagina, uterus, and urethra are washed with antiseptic fluids.
Transdermal Route
In the transdermal route, the drug in the form of patches is applied to the skin and the drug is absorbed.
This route is used for lipophilic drugs.
Transdermal medications are administered through the skin in the form of patches of different drugs.
Inhalational Route
In this route drug in form of aerosols or fine powders is administered through inhalation and directly reaches to the lungs.
This route is used for both local and systemic effects.
Usually, this route is used for asthmatic patients for rapid action.
Also Read:
No comments:
Post a Comment