In medicine, the term bolus is used to refer to a drug that is given to a patient in order to increase concentration in the blood. Usually, a bolus is a small ball of medicine. There are a number of different ways that a bolus can be delivered such as intravenously and intramuscularly. A common example of a bolus is the administration of insulin to people who suffer from diabetes. A bolus is also the name given to a large pill that is given to cattle and other animals in order to prevent dehydration.
Where the bolus is administered in the body is an important factor in order to ensure that the medication reaches the correct concentration in the appropriate time. The purpose is to raise the concentration to an effective level — the level at which 50% of people see the desired response from a particular drug. For this reason the placement of the medical pill depends on the current concentration levels in the body.
The method of delivery also depends on the desired effect. For example, the medication may be given intramuscularly in order to provide a slow release. This is especially useful during the injection of vaccines that need to develop the body’s immune system over time. Subcutaneous injections, on the other hand, are commonly used by drug addicts.
An intravenous injection is the most effective at increasing the concentration quickly. For this reason it is most commonly used when it’s important to raise concentrations in a timely manner such as after a treatment. Intravenous injections of medicine are also commonly used after medicine has been removed from the body of a patient.
Many health care workers regularly refer to a bolus as a dose of insulin that is quick to act. A diabetes dosage must be taken during a meal as it is fast acting. On the other hand, there are methods of insulin administration that are much slower to act and hence are used for other purposes. For example, a basal rate provides a much slower dose of insulin.
The term is also used for some drugs given to animals by a veterinary professional. These are used for a number of different purposes including to counteract kidney problems and to act as a slow release dehydration tablet. Due to the fact that there are several minutes between administration and absorption, during this time the medicine is a bolus.