Making Sense of Medication Classification
A drug class is a group of medications with similar properties.
It also describes different classification systems and their distinct purposes.
Multiple Categories of Classification
Not all drugs fit neatly into a single category.
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Some drugs are grouped together under one classification method but not another.
Some have multiple classifications.
For example,antacidswork by blocking stomach acid in people withchronic gastritisorgastroesophageal reflux disease (GERD).
Toxicity can also occur if you take two drugs of the same class at the same time.
This same enzyme is also responsible for the production of a blood-clotting chemical called thromboxane A2.
Taking Advil and Aleve can amplify this effect and even lead to internal bleeding andkidney failureif used in excess.
Assessing Drug Resistance
Medications used to treat chronic infections have the potential for drug resistance.
When resistance develops, a drug may be far less effective or not work at all.
To make matters worse, resistance to one drug often confers resistance to every other drug in the class.
Some drugs and drug classes are more vulnerable to resistance than others.
The same applies to antibiotics.
The overuse of antibiotics has led to increasing patterns ofantibiotic resistanceworldwide.
This is especially true with drugs that act on thecentral nervous system.
A prime example of this isfentanyl, an opioid drug painkiller.
ATC Classification System
The thousands of drug classes and subclasses can be classified in several ways.
ATC categorizes drugs based on five levels from the broadest to the most specific, using letters and numbers.
This system is meant for healthcare providers and isn’t useful to patients.
But the strict hierarchy it establishes protects people from drug errors (like getting the wrong one.)
Its goal is to ensure prescription and OTC drugs approved in the U.S. meet quality standards.
Among its many functions, the USP was tasked by the U.S. Congress to classify drugs.
It helps guide healthcare providers when it comes to prescribing drugs under the Medicare Prescription Drug Benefit.
Worldwide, dozens of countries have national pharmacopeias and there are also regional pharmacopeias such as the European Pharmacopoeia.
Other countries rely on the International Pharmacopeia maintained by the WHO.
The USP classifies drugs in a far broader way than the ACT system.
Summary
Drug classifications are important.
The main classification systems are ATC and USP.
They use different methods but both are useful tools.
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