Sometimes doctors come across symptoms that remain unexplained despite extensive investigations. When no clear medical explanation is found and symptoms persist, patients often progress worry and/or depression as a result of living with an unresolved health problem.
In these situations, treatment often focuses on the emotional consequences, and the underlying medical mystery remains unsolved.
Yet sometimes the right question can reveal a surprisingly simple explanation and an equally simple solution.
Case Study: Chronic Cough
Linda was 54 years old when she came to see me with a persistent dry cough of 14 months’ duration.
The cough was relatively mild during the day, but became persistent at night. He described a constant tickling sensation in his throat. Coughing relieves the sensation for a short time, but within seconds the tickle will cause coughing again.
He tried drinking cold water, warm water, and various home remedies, but nothing lasted long. A chronic cough disturbed his sleep day and night, and he was weak during the day.
As the months passed, Linda became increasingly anxious and depressed.
Apart from being treated for cough and high blood pressure, he was healthy, exercising regularly and eating a balanced diet. diet.
Linda had never smoked and had no history of asthma. His physical examination was normal. Blood tests and chest X-ray were unremarkable.
Over the past year, he has consulted several specialists.
An ear, nose, and throat (ENT) specialist performed a laryngoscopy to check for throat irritation but found no abnormalities. There was no evidence of any inflammation and postnasal drip.
An internist suspected gastroesophageal reflux disease (GERD) and thought stomach acid might be irritating his throat at night. Linda was prescribed a proton pump inhibitor for three months, but her symptoms did not improve.
Another doctor, concerned about the possibility of early lung cancer, ordered a chest CT scan. The scan was normal.
Fourteen months after the onset of the cough, Linda was still suffering.
As no explanation was found and her anxiety and depression worsened, she had to be referred to a psychiatrist when she came to see me.
This is the question that solved the mystery
The most important question turned out to be surprisingly simple:
“What medications are you taking?”
When I reviewed Linda’s medications, I discovered that she was taking an ACE inhibitor to treat her high blood pressure.
Suddenly everything made sense.
Maybe he was guilty drug himself.
What the research shows
Linda’s experience is not unique.
ACE inhibitors (angiotensin-converting enzyme inhibitors), a common blood pressure medication, are known to cause chronic dry cough in about 5-25% of patients. Side effects are more common in women and non-smokers. A cough may begin soon after treatment, but it may occur months or even years later. (1) (2) (3)
The simplest way to confirm the diagnosis is to stop ACE inhibitors and switch to another class of blood pressure medication. In most patients, the cough improves within a few days to a few weeks. If the offending drug is restarted, the cough often returns. (4)
Interestingly, this side effect is usually not dose dependent. Even low doses can cause coughing in genetically susceptible individuals. (5)
Studies show that ACE inhibitors lower the threshold of the cough reflex in susceptible patients. As a result, simple environmental stimuli that would not normally trigger a cough can suddenly trigger persistent symptoms. (6)
what happened to linda
I stopped Linda’s ACE inhibitor and replaced it with a calcium channel blocker, a different class of blood pressure medication.
Within a week, his cough was gone.
For the first time in over a year, he was able to sleep through the night. As her sleep improved and her physical symptoms disappeared, so did her anxiety and depression — without needing to. psychiatric drug.
His blood pressure was well under control.
Psychological lesson
Linda’s story illustrates an important principle in both medicine and psychology.
When symptoms remain elusive, it can be tempting to focus solely on treating their emotional consequences. However, anxiety and depression are often understandable reactions to persistent physical symptoms. Whenever possible, it is important to identify and eliminate the root cause rather than treating only the effects.
Before concluding that a symptom is unexplained or untreatable, doctors should carefully review all prescription medications, over-the-counter products, and supplements. Sometimes the answer is hidden in plain sight.
along my careerI have met many patients with chronic dry cough who were treated with allergy medications, acid-reflux therapy, and other interventions while ignoring the root cause—an ACE inhibitor. In some cases, the drug is hidden inside the combination blood pressure pills, which makes it easy to miss.
Medicine is both a science and an art. Laboratory tests and imaging studies are invaluable tools, but careful listening and thoughtful questioning are equally important.
Sometimes the key to solving a medical mystery isn’t ordering another test—it’s just one more question.
Copyright 2026 @Chris Gilbert, MD, Ph.D.
