Simple Guide to How Drugs Work in Your Body

Pharmokinetics is the term used for how drugs work the body. They work by 4 critical points: Absorption, Distribution, Metabolism and Excretion.

The 1^st to absorbing medication is by absorption, this is the movement of the medication through one or more membranes of the body. Eventually the drug will reach its targeted cells. As a nurse we need to know any barriers that would cause the medication not to reach its designated area for example, foods or hair on skin (patches).

The second component to medications working in the body would be distribution; this happens after medication is absorbed, the medication is then transported after absorption or through direct administration to the blood system. There are few factors relating to interference with distribution that deals with binding. Binding would be when the medication attaches to a plasma protein, sometimes this plasma protein will hold onto the medication a bit longer then it should causing the medication to not reach its designated source cell.

The third point would be metabolism. The metabolism is the total of all chemical reactions in the body. This occurs in every single cell of the body, but the primary site is the liver. (This is why medication toxicity happens mostly in the liver). The chemical reactions in the body deactivate the medication.

The fourth point would be excretion; this would be the elimination of the medication. Most medications are removed from the body either by urination, defecation, perspiration or by exhalation. The main organ that deals with excretion is your liver.

There are many factors that can affect the influence of how effective medications are in your body. These factors include what is known as half life. Half life is the length of time that is required by a medication concentration in the plasma to reduce by half.

Other factors include, genetics, metabolic rate, ever changing medical conditions, dose of medication, excretion rate, and frequency of dosing, food interactions, drug interactions, and absorption rates.

Understand that drugs activate specific receptors to produce the responses needed will also help the nurse understand any normal side effects when dealing with medication. A receptor drug will attach to a receptor and the bind with it. An agonist's drug is capable of binding with a receptor causing a chemical reaction. A antagonist drug will inhibit or block the response of an agonist.

As a nurse or student nurse you should never give a medication without knowing what that medication is used for, the correct dosing, the dosage guidelines, the possible side effects and what the desired outcomes of the medication are.