2 September 2026

My patient thought she had a hernia. Was she just stoned?

Since coming to Canada, I regularly meet long-term daily cannabis users

Women in their late thirties aren’t often accompanied to doctor’s appointments by their mothers, so I made sure to be extra friendly and welcoming. The parental presence could imply a vulnerable patient, or possibly someone at the end of their tether with the health system – the maternal big guns were being rolled out to emphasise that “something must be done”. Either way, I wanted us all to get off on the right foot.

“It’s my hernia!” Kelly started. “I was in hospital again last week. It keeps happening – the pain, the vomiting. Every time I go in, they just give me pain injections and send me home.”

This did sound puzzling; a hernia causing pain and vomiting might be obstructed – a medical emergency requiring immediate surgery. “Whereabouts is it?”

She gesticulated towards her upper abdomen and lower chest. Most hernias are in the groin or upper thighs. The penny dropped. I asked if she meant a hiatus hernia, in which a portion of the stomach has pushed up through the diaphragm and lies in the chest.

“Yes! They found it with that camera thing.”

Investigating Kelly’s recurring bouts, the hospital had organised numerous tests. Blood tests and a CT scan had ruled out gallstones and pancreatitis; to check for stomach ulcers, she’d had a gastroscopy. The endoscopist had commented on a hiatus hernia, a common scenario that can cause heartburn and indigestion. But I’ve never known one to create the acute pain and vomiting Kelly had been experiencing.

On my computer, I opened her most recent A&E discharge summary. I was struggling to imagine another doctor attributing her symptoms to a hiatus hernia, so I thought I’d better get a handle on things before continuing the discussion. I skimmed through the summary of all the investigations to date and got to the diagnostic conclusion: cannabinoid hyperemesis syndrome (CHS). The casualty officer’s notes stated that he’d explained the problem and what to do about it. No mention of Kelly’s hiatus hernia at all.

CHS is not something I had ever come across in the UK, but this was now my second case since coming to Canada. It afflicts some long-term daily cannabis users, producing exactly the sporadic episodes Kelly was describing. There is no confirmatory test, so you have to exclude various conditions that can present in the same way. Cannabis is legal in Canada, meaning patients are more likely to give an honest account of their usage to inquisitive doctors. It also means it is freely available, and remarkably cheap, so can easily become a large part of people’s lives.

“What did the doctor at the hospital say about it all?”

Kelly shrugged. “He didn’t say anything. Just gave me the injection and sent me home.”

Either Kelly was right and, despite what he had written in the discharge note, the casualty officer had ducked the issue. Or his words had fallen on deaf ears. I made direct eye-contact: “These attacks you keep getting: I promise you, they’re nothing to do with your hiatus hernia.” I showed her the letter and talked her through the reasoning behind the diagnosis.

“She’ll have to give it up, won’t she?” This was the first time Kelly’s mother, arms folded, had spoken.

I nodded. “It’s the only cure.” I printed out some information about CHS and gave it to Kelly. “Have a read, it’ll all make sense.”

Attacks of CHS strike randomly, without the patient doing anything differently from any other day. It makes the diagnosis hard to accept because the links between cause and effect are obscure. Kelly had latched on to her hiatus hernia as the explanation – especially as everything she read about “hernias” online told her she was right. But I noted the absence of surprise when I showed her what the casualty officer had written. And then I understood the reason for her mum’s attendance. Sometimes it requires a pincer movement to drive an unwelcome message home.

[Further reading: Why does cancer progress for some while for others the disease remains dormant?]