INJECTIONS

INJECTIONS

Injections are parenteral therapy. It means giving of therapeutic agents including food outside the alimentary tract.

An injection is the forcing of a fluid into a cavity, a blood vessel or body tissue through a hollow tube or needle

Purpose

To get a rapid and systemic effect of the drug
To provide the needed effect even when the patient is unconscious
Assures that the total dosage will be administered and the same will be absorbed for the systemic action of the drug
Provides the only means of administration for medications that cannot be given orally
To obtain a local effect at the sight of the injection
To restore blood volume by replacing the fluid, e.g. in shock conditions
To give nourishment when it cannot be taken by

Types of Injections

Intradermal: drug introduced into the dermis
Subcutaneous: drug introduced into the subcutaneous tissue
Intramuscular: injected into the muscles
Intravenous: introduced into the vein
Intraspinal: introduced into the spinal cavity
Intra-osseous: introduced into the peritoneal cavity
Venesection: opening a vein and introducing a tube or wide bore needle and introducing medicines an fluids or taking out blood
Infusions: when a large quantity of medicines as fluids are to be introduced into the body
Transfusions: it is the introduction of whole blood or plasma into a vein or artery

Factors that Favors Absorption

Blood supply to the area: fluids injected into the blood stream will act quicker than any other methods used
The composition of the fluid injected: solubility and diffusibility of the fluid
Application of heat: heat dilates the blood vessels; therefore the heat applied over the site of injection increases the rate of absorption
Massage: it stimulates the local blood supply and increases the rate of absorption
Circulation time of the blood: absorption of medicines and fluids injected to the body will diminished in a person who has venous congestion (edema)
Physical condition: the local disease condition of the skin and underlying tissues such as skin lesions, inflammations, etc. delays the absorption of the drug
Addition of the substances: that tends to breakdown the natural resistance of the tissues can increase the rate of absorption

Complication of Injections