When you have fibromyalgia (FMS) and chronic fatigue syndrome (ME/CFS), you can end up taking a lot of different medications, including common medications for pain. While that may help you feel and function better, it can also be dangerous. It pays to really understand the drugs that are available to you.

Several types of painkillers are available over the counter (OTC), and a large percentage of us are given prescription painkillers at some point in our illness. These drugs each have their own dangers and possible side effects, and some can interact badly with other medications.

Common NSAIDs

One of the most common types of painkillers is anti-inflammatory drugs. A commonly used type of anti-inflammatories is called NSAIDs, which stands for non-steroidal anti-inflammatory drugs. Popular OTC NSAIDs include:

These drugs are also available in prescriptions strengths. Prescription-only NSAIDs include:

Most of us are familiar with the use of NSAIDs to reduce pain caused by inflammation. However, some NSAIDs may alleviate pain by blocking particular enzymes that are part of your body's response to painful stimuli. It's not clear whether this mechanism is effective against the unusual pain types associated with FMS.

For this reason, the trend with doctors is to prescribe fewer NSAIDs and instead prescribe drugs that work on the central nervous system, which is where our pain is believed to stem from. That's according to research published in a 2013 issue of the European Journal of Medicine.

Some studies suggest that inflammation plays a key role in ME/CFS. Is FMS inflammatory, though? It's generally considered not to be, but a study authored by Ginevra Liptan, MD, suggests that it does involve inflammation of the fascia.

Regardless of the specific roles of inflammation in these conditions, we know that many people take NSAIDs for FMS and ME/CFS-related pain, and some with these illnesses also take NSAIDs for other medical problems that involve inflammation.

Risks

While you can find NSAIDs in most homes and buy them almost anywhere, they do still come with serious risks.

According to the American Journal of Medicine, more than 100,000 people are hospitalized due to NSAIDs each year in the U.S. Additionally, 15-20,000 die each year from NSAID-related problems such as ulcers and gastrointestinal bleeding, and as many as 60 percent of NSAID users may develop digestive side effects.

NSAIDs are also linked to an increased risk of dying from heart attack or stroke. These drugs can lead to liver or kidney problems, as well.

Taking two NSAIDs together is dangerous—a 2004 study published in the European Journal of Clinical Pharmacology showed that it increased the risk of liver injury or kidney failure by 500-600 percent over the use of a single NSAID.

Long-term use, such as you'd expect with a chronic condition, may increase these risks.

Some of the problems stemming from NSAID use may be due to people's attitudes toward OTC drugs. They may think they're not important or dangerous and therefore don't report use to their doctor or pharmacist. It's crucial that these health professionals know everything you're taking, including OTC drugs and dietary supplements, so they can help you avoid serious problems.

Side Effects and Interactions

In addition to the above risks, NSAIDs can cause several side effects. The most common ones are:

Nausea
Vomiting
Diarrhea
Constipation
Decreases in appetite
Rash
Dizziness
Headache
Drowsiness

Some of these side effects (digestive problems, dizziness, headache, drowsiness) are also common symptoms of FMS and ME/CFS. When you start taking a new NSAID, it's important to note any changes in symptoms that may be due to the medication.

NSAIDs can interact negatively with several other drugs, so be sure to talk to your doctor and pharmacist about all of your medications.

Because NSAIDs reduce your blood's ability to clot, it can be dangerous to combine them with anticoagulants (blood thinners) such as Coumadin (warfarin).

If you're being treated for hypertension (high blood pressure), you need to know that NSAIDs may make your medication less effective.

Reducing Your Risk

According to the FDA, to protect your health you should only use NSAIDs exactly as prescribed, at the lowest possible dose, and for as short a time as you can.

When your pain is chronic, that last recommendation is difficult to follow. Be sure to report any increase in side effects to your doctor. Your doctor may want to monitor markers of liver health if you're taking NSAIDs long-term.

Smoking cigarettes and drinking alcohol can increase your risk of NSAID-related ulcers or bleeding problems, both of which can cause strike without warning and can kill you. Be sure your doctor knows about your smoking and alcohol use.

A Word From Verywell

You and your doctor should decide together whether NSAIDs are appropriate for you, based on your diagnoses, symptoms, overall health and lifestyle factors. It's important to note that one NSAID may work better for you than others, so it may take experimentation with different drugs to achieve the best results.

If you don't feel NSAIDs are effective at reducing your pain, talk to your doctor about possible alternatives and weigh the risk against the benefits.