Pain Medication Side Effects

Over the counter (OTC) and prescription-strength pain medications can help relieve discomfort and physical distress, but they can cause side effects too. You might not have any side effects when you use certain pain medications, or you can experience side effects that could be mild, limited, or severe and intolerable from taking some medications.

OTC pain medication side effects can include allergic reactions, stomach upset, bruising, dizziness, and more—and side effects don't affect everyone in the same way.

Woman wearing a head scarf holding a pill bottle and taking a pill
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Side Effects and Pain Relief — a Trade-Off?

You and your healthcare provider are in the best position to decide whether you are at risk of developing side effects, and which side effects you are more predisposed to. Rest assured that you might be susceptible to side effects from some medications, but you are likely to be able to tolerate several pain medications too.

For example, if you have a history of ulcers, you might be better off avoiding anti-inflammatory medications. But if you have trouble sleeping, you should steer away from pain medications that are known to interfere with sleep.

How to Find Side Effects of Drugs You're Considering

When taking over the counter drugs, you should read the label for side effects, then weigh these possibilities against the pain relief benefit you expect to get from taking the medicine. Ask your pharmacist or your healthcare provider about anything you don't understand.

Note that some side effects constitute a medical emergency; an example is having an allergic reaction to the drug.

Learn how to recognize the signs of an allergic reaction and be prepared to call for emergency help if you start to have symptoms such as:

  • Itching
  • Hives
  • Rash
  • Mouth or facial swelling
  • Shortness of breath

If your healthcare provider prescribes medication, you can have a discussion about the anticipated risks and benefits. Your prescription will come with a label that lists the side effects associated with the drug.

Are the Risks of Opioids Worth It?

Opioids are powerful prescription pain medications, usually used for severe, short-term pain, like post-operative pain or pain due to a severe traumatic injury.

Some adverse effects of opioids include but are not limited to:

  • Common side effects include constipation, nausea, sedation, and an increased risk of falls and fractures.
  • Chronic use can lead to depression, and/or sexual dysfunction.
  • As narcotics, opioids also come with the risk of addiction. This could change your life for the long term, as addiction is very difficult to overcome.
  • And, opioid overdose—accidental or deliberate—can lead to death. In fact, one of the main reasons the CDC published a guideline on opioid prescribing was because of the number of opioid-related overdoses and deaths from overdose.

The Centers for Disease Control and Prevention (CDC) recommends that practitioners not prescribe opioids as a first-line treatment for chronic back pain. The CDC recommends that healthcare providers initially treat patients with chronic back or neck pain using non-drug therapies or medications other than opioids, and opioids should be used only if expected benefits for both pain and function are anticipated to outweigh risks to the patient.

A 2015 study reports while opioids are the most commonly prescribed painkillers in the U.S. (with more than half of regular opioid users experiencing back pain), they aren't proven to help people return to work faster, nor do they improve functioning when used for treatment of an acute episode.

The study also states that reviews of the medical literature found “scant evidence” that opioids are effective for treating chronic back pain. Additionally the study showed that for all types of non-cancer pain — which includes, but is not limited to, neck and back pain — the effectiveness of opioids is about 30% for short term pain relief and did not improve physical functioning.

A suspected opioid overdose should be quickly treated with naloxone hydrochloride. In 2023, the FDA approved Narcan (naloxone hydrochloride) Nasal Spray and RiVive (naloxone hydrochloride) nasal spray as OTC emergency treatments for a known or suspected opioid overdose. 

Side Effects Comparisons

Here are a few examples of common medications used to treat back pain.

Active Ingredient Brand Name Drug Class OTC or Prescribed? Side Effects
Ibuprofen Advil NSAID Available OTC GI-related symptoms, Reye's Syndrome in children
Naproxen Aleve and others NSAID Available as both (depending on strength) GI-related symptoms, headache
Acetaminophen Tylenol and generic and others Analgesic (pain reliever) Available as both (can be prescribed with codeine as well) Potential liver damage
Pregabalin Lyrica Anticonvulsant Prescribed (FDA-approved for shingles pain, neuropathy in diabetes. Other uses off-label) Dizziness, drowsiness swelling, weight gain
Gabapentin Neurontin Anticonvulsant Prescribed (FDA-approved for shingles pain) Dizziness, drowsiness, allergic reaction, withdrawal seizures
3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. American Academy of Allergy, Asthma & Immunology. Anaphylaxis Symptoms & Diagnosis.

  2. Plein LM, Rittner HL. Opioids and the immune system – friend or foe. British Journal of Pharmacology. 2018;175(14):2717-2725. doi.10.1111/bph.13750. Published July, 2018.

  3. Deyo RA, Von Korff M, Duhrkoop D. Opioids for low back pain. BMJ. 2015;350(jan05 10):g6380-g6380. doi. 10.1136/bmj.g6380. Published January, 2015.

Additional Reading

By Anne Asher, CPT
Anne Asher, ACE-certified personal trainer, health coach, and orthopedic exercise specialist, is a back and neck pain expert.