Chances are, if you visit a hospital, emergency room, or family doctor’s office for an injury or illness, you’ll be prescribed a medication to either relieve your symptoms, clear an infection, or remedy some dysfunction.

There are thousands of ways to classify medications. It’s quite a chaotic system because of the sheer number of drugs and categories. But at Trusted ER, our emergency physicians always plainly explain what a medication does and why we’re using it. In this article, you’ll learn the basics of a few common categories of medication — ones that you may come into contact with if you visit an ER. 

How medications are classified

Part of the reason that drug classification is chaotic is that there’s more than one way to organize drugs. We classify drugs in the following ways: 

• By their use (what condition they treat, e.g., an ACE inhibitor treats high blood pressure)
• By their mechanism of action (biochemical reactions that take place when you take the medication, e.g., slows the activity of the ACE enzyme)
• By their mode of action (how your body responds to the drug, e.g., your blood vessels relax and your blood pressure decreases).  
• By their chemical structure (what the drug is made of)

The United States Pharmacopeia (USP) established a drug classification system where they categorize medication first by their use, then by categorization of mechanism and mode of action, and finally, by chemical makeup. There are other classification systems, but the USP system is most useful to consumers. 

Common classifications of medications

Below are several groups of drugs that you may be prescribed after a visit to the emergency room, or that you might be given during an ER visit. Keep in mind that these aren’t all of the categories designated by the USP (there are nearly 50), but these are common. 

Analgesics: These are pain medications, including both opioids and non-opioids. These may act on substances in the body that cause pain, interrupt pain signals to your brain, relieve inflammation, or work by some other mechanism. 

Anesthetics: These medications block the sensation of pain and other feelings, such as discomfort or anxiety. We usually use these so that we can perform surgery or other treatments. Anesthetics may be local to a pain or surgery site or general, of which the aim is usually partial or complete unconsciousness. You may be given anesthetics orally, as an injection, via inhalation, or as a topical salve. 

Anti-inflammatory agents: This most often refers to non-steroidal anti-inflammatory drugs (NSAIDs), such as Tylenol® and Ibuprofen. These drugs primarily reduce pain, lower inflammation, and reduce fevers. Another conventional anti-inflammatory medication is a COX-2 inhibitor, which reduces the activity of certain compounds that irritate your body.

Antibiotics: This is a large class of medications that intends to treat bacterial infections of all kinds, from urinary tract infections to upper respiratory infections to pink eye. There’s no single antibiotic that can cure all infections, and it’s sometimes a tricky game figuring out which antibiotic will work best (based on your condition, medical history, antibiotic resistance, and more).

Antivirals: Antiviral drugs, such as the common Tamiflu for influenza, work by interfering with the virus. It’s important to know that antivirals don’t kill the virus, but they do keep it from spreading within your body. They may also help manage symptoms while your body fights off the virus. 

To learn more about medications and how we use them, visit our pharmacy FAQ page. Trusted ER is a 24-hour independent emergency room — call one of our convenient Texas locations for more information.