Clinical case review
Review the complete Pharmacy case, its five progressive clues, the diagnosis, and the clinical reasoning behind the answer.
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WhatsTheDx publishes a new Pharmacy case every day. Five clues, one diagnosis, and no account needed to play.
Play today's Pharmacy caseThese are the case findings in their original reveal order, moving from the broader presentation to the most discriminating evidence.
Clue 1
A 41-year-old comes into the pharmacy holding on to the counter. He got home from a week away yesterday and has felt wrong for four days: the room swings when he turns his head, he crosses a room with a hand on the furniture, his head aches, and his arms and legs are heavy and sore in the way they are when flu is coming.
Clue 2
Sleep has gone strange along with it. His dreams are vivid enough to wake him, he is up at three in the morning, and he has snapped at his partner twice and then cried about something trivial — none of which is like him. He is queasy most of the day.
Clue 3
One tablet has been part of his morning for four years. It was on the kitchen counter when the taxi arrived, and he flew out without it — the last dose was seven days ago and he has not started it again. For the first two days he felt fine. It was the third day without it that everything began.
Clue 4
There is one symptom he saves for last because it sounds mad. When he moves his eyes sideways a jolt goes through his head — a fraction of a second, like a camera flash he can feel rather than see — and sometimes it runs down the back of his neck. His fingers tingle. He is frightened this means the illness is coming back, although his mood has been steady all year, with no low mood, no loss of interest, and no hopelessness before this started.
Clue 5
Everything measurable is unremarkable. Temperature 36.8 °C, pulse 78, blood pressure 124/78. He is alert and oriented, reflexes normal and symmetrical, no clonus, no rigidity, no agitation. The urine toxicology screen is negative and the metabolic panel — sodium, potassium, glucose, renal and hepatic values — sits inside the reference limits. Nothing has been added to his medicines. One thing was subtracted.
Diagnosis
This is antidepressant withdrawal — a discontinuation syndrome — and not a relapse. The timeline is the first giveaway: the last dose was seven days ago, two days passed uneventfully, and the symptoms arrived on the third day. Withdrawal symptoms usually appear within a few days of stopping the drug or of reducing the dose, whereas a returning depressive illness re-emerges over weeks. The symptom set is the second giveaway. Dizziness, imbalance, headache, flu-like aching, insomnia with increased dreaming, irritability, crying, and nausea are all recognised withdrawal features — and the electric shock sensations, the "zaps", with their sensory disturbance belong to withdrawal rather than to depression or to an anxiety disorder. This is common rather than exotic: one to two-thirds of patients have at least one new symptom when an antidepressant is stopped abruptly, and withdrawal symptoms occur in at least one-third of those who stop. The incidence is higher with short half-life agents such as paroxetine and venlafaxine than with long half-life ones such as fluoxetine, whose long-lived metabolite norfluoxetine effectively tapers the patient down on its own. Paroxetine is the hardest of the group to leave: symptoms on stopping are more common and more severe with it than with other SSRIs, which may be due in part to the fact that it inhibits its own metabolism. It is worth being explicit about what this is not. Serotonin syndrome is the other drug-related emergency in this space, but it follows overdose or the combination of multiple serotonergic medications — adding, not removing — and it brings mental status changes, autonomic dysfunction, hyperthermia, hyperreflexia, and clonus. None of that is here: temperature 36.8 °C, pulse 78/min, blood pressure 124/78 mm Hg, alert and fully oriented, reflexes normal and symmetrical with no clonus. Management is reassuring. Most symptoms resolve within 2 weeks, though severe and prolonged withdrawal lasting weeks to months has been reported, and the way to avoid the whole episode is to reduce the dose gradually over weeks rather than stopping abruptly. One caution belongs with every case of this kind: recurrent depressive symptoms or increased suicidality after stopping may represent withdrawal or a genuine re-emergence of the original condition, so both questions have to be held open rather than one being assumed.
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Open the clinical referenceFor education and entertainment only. This fictional case is not medical advice and does not replace supervised clinical training, diagnosis, or treatment.
