The Lucky 7: Classes of Meds for Pain Management

Pain management is basically a dirty word among nurse practitioners and physician assistants today. We shun patients on long-term pain medications and grow weary of requests for "that medicine that I had that one time - it starts with a 'D'...". The opioid problem and our resulting hesitancy to prescribe pain medications has become so bad that a patient comes to see us with something like an acute femur fracture and we pause before prescribing ten tablets of Percocet upon discharge from the hospital. 

While the nation's opioid crisis paired with regulatory organizations' view that "pain is a vital sign" has put us in a tough spot as providers, the reality is that pain does happen and often necessitates treatment. I've never fractured a femur but I'm pretty certain I'd want a few doses of Percocet to go home with should I suffer from one. So, what's an NP/PA to do when a patient presents requesting pain control?

Consider the seven categories of pain medications. There are plenty more than just opioids out there. 

1. Acetaminophen

Often we turn to acetaminophen for its antipyretic properties, but Tylenol is also a fantastic go-to for pain relief. A centrally acting agent, Tylenol's analgesic properties are likely due to COX inhibition and elevation of the pain threshold. Acetaminophen has some mild anti-inflammatory effects but also provides good 'ole generalized pain relief. 

2. NSAIDs

Non-steroidal anti-inflammatory drugs (NSAIDs) are a pain relief staple. And, a favorite among providers skirting opioid prescribing. NSAIDs work by targeting COX receptors (some COX-1, some COX-2, and some target both). What are COX receptors, you ask? The COX enzyme system works to synthesize prostaglandins, which are responsible for inflammation. Blocking this pathway has anti-inflammatory effects. We run into a few side effects with blocking COX and its resulting pathways. COX-1 is expressed, for example, in the GI tract as well as in platelet function. So, you'll want to familiarize yourself with NSAID prescribing considerations before going crazy with these helpful drugs. 

3. Antidepressants

As I talked about in a previous post on prescribing for pain, the first step in treating pain is to determine its origin. For patients with neuropathic pain, antidepressants can be a lifesaver. Because antidepressants modulate neurotransmitters like serotonin and norepinephrine and therefore nerve activity they can be incredibly helpful to patients with chronic neuropathic pain. SNRIs like venlafaxine, duloxetine and bupropion have been shown to be particularly effective. TCAs are also effective for pain relief, but come with a lengthy list of drug-drug interactions so use caution here. Don't forget that antidepressants take a while to kick in so avoid major dose adjustments until you've given the med a fair shot at working. 

4. Steroids

Steroids work on inflammatory pathways by reducing prostaglandin synthesis. They have been promoted as a beneficial way to reduce pain, especially pain that is inflammatory or musculoskeletal in nature. They may be used alone or as an adjunct to other therapies. Corticosteroids do have a lengthy side effect profile so you'll want to weigh the risk to benefit ratio before prescribing that pill pack. 

5. Anticonvulsants

Like antidepressants, anticonvulsants regulate neural activity. So, they're effective for many kinds of neuropathic pain. Neuropathy, for example, may be treated with gabapentin or pregabalin. These medications work by inhibiting neurotransmitters and therefore suppress neural activity that signals pain. 

6. Opioids

Opioids don't address the source of pain by decreasing inflammation or neural activity like other meds in this list. Rather, they inhibit your body's ability to feel pain. Opioids act like your body's own natural endorphins, the chemicals that make you euphoric (think runner's high). As we're well aware, they come with some pretty serious side effects ranging from constipation to severe addiction. opioids are classified by strength (potency) and duration of action, both of which we'll look at in another post. 

7. Other

Tramadol is an interesting drug. It has antidepressant-like properties along with opioid properties. Tramadol was recently added to the list of scheduled drugs and is now considered a controlled substance. While the pairing of these two pain relieving properties sounds ideal, tramadol has a bunch of side effects and can cause serotonin syndrome, especially in patients who are also taking antidepressants. Prescribe with caution. 

 

Comments

Exellent explanation of different approaches to oral pain medications.

Kim Lilly-Bernau