Detailed guides to painful problems, treatments & more

“Primary” versus “functional” pain

 •  • by Paul Ingraham
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Weekly nuggets of pain science news and insight, usually 100-300 words, with the occasional longer post. The blog is the “director’s commentary” on the core content of PainScience.com: a library of major articles and books about common painful problems and popular treatments. See the blog archives or updates for the whole site.

A “primary” headache is basically an unexplained headache: a headache without an obvious cause. The headache is the main thing, not a symptom of some other thing we know about.

Primary is standard terminology and (appropriately) emotional neutral.

Weirdly, unexplained primary pain problems in other parts of the body are often called “functional pain disorders” … and this term is not neutral. In fact, it’s kind of an asshole of a term with a lot of shameful historical baggage. If terms were people, this one would be your racist uncle.

Originally tamer, over the last several decades “functional pain” gradually became obnoxious doctor-code for “probably psychosomatic”: because if we don’t know how to explain it, it must be all in your head, right? Obviously! This classic argumentum ad ignorantiam — argument from ignorance — got enshrined in jargon and became one of the great shames of medicine. It really needs to go away.

Schechter NL. Functional pain: time for a new name. JAMA Pediatr. 2014 Aug;168(8):693–4. PubMed #24887181 ❐

Schecter explains several problems with the term “functional pain disorder,” and particularly highlights its strong and ridiculous connotation of a psychological problem in modern usage. He proposes a tidier and more neutral description: “primary pain disorder.”

Therefore, a new neutral name is proposed for this category, primary pain disorders. This term arises from the headache field, where headaches are categorized as primary (the head pain itself is the central problem) or secondary (the headache is due to other factors such as increased intracranial pressure or infection, for example). The term primary pain disorder implies that the pain itself is the disease.

It’s nice that primary headache has mostly escaped the stink of the “functional” label, but diseases like fibromyalgia and irritable bowel syndrome are hopelessly mired in it. They should also be called “primary pain” problems, I believe. Primary headaches are mostly thought of as legitimately unexplained, with much less judgement.

Why would that be? Probably because unexplained headaches are so common that they frequently afflict the self-same doctors that would otherwise get condescending and dismissive! And so, although primary headaches are often considered an example of a “functional pain disorder,” they are rarely called that.

Unexplained headache free of judgemental baggage? Surely you jest!

Some readers are now hollering at the screen:

Are you *#%[email protected]^% kidding me? I had a neurologist tell me that I have migraines because I’m an excessively ‘willful’ woman! Right to my face! In 2019!

That diagnostic crime isn’t yet extinct. Headache/migraine obviously haven’t entirely avoided the same stigma suffered by other primary pain disorders. While it’s refreshing that the term “functional” is applied to headaches less often, the diagnostic buck has been passed to psychiatrists all too often, especially for migraine. You can bet that many female migraineurs throughout history have been told they were “hysterical,” and that is appalling.

This is an excerpt from a recent update to my headache tutorial, and it continues with a discussion of the role of the mind and stress in headache. I’ve also updated my article about types of pain with “functional pain.”