Clinical Cases in Pharmacology Clinical Cases  ·  Psychiatry II  ·  Anxiety  ·  Cannabidiol (CBD) for Anxiety: Real Use Against Limited, Mixed Evidence
Psychiatry, Case 0015 — Anxiety

Cannabidiol (CBD) for Anxiety: Real Use Against Limited, Mixed Evidence

A patient self-treating his anxiety with unmeasured over-the-counter CBD asks if he should just skip prescription medication altogether. The honest answer runs into both a genuinely mixed evidence base and a largely unregulated supplement market.

Abbreviations, terms, and other agents mentioned in this case GAD — generalized anxiety disorder  ·  CBD — cannabidiol  ·  OTC — over-the-counter  ·  SSRI — selective serotonin reuptake inhibitor
Presentation

Ben H., a 27-year-old man, has mild-to-moderate generalized anxiety disorder and has been taking an over-the-counter CBD tincture, purchased online, for the past three months at a dose he estimates but has never precisely measured. He reports it "takes the edge off" without any of the daytime sedation he experienced on a brief prior trial of hydroxyzine, and asks his physician directly whether he should just continue with the CBD instead of starting a prescription medication, since it's "natural" and available without a prescription.

CBD's anxiolytic evidence is genuinely mixed and considerably thinner than any FDA-approved anxiety treatment — some controlled trials show real anxiolytic effect, particularly at doses well above what most over-the-counter products actually contain, while others show no meaningful difference from placebo. Critically, the supplement market is essentially unregulated for potency and purity: independent testing of over-the-counter CBD products has repeatedly found significant mislabeling, with actual CBD content often well below, and occasionally well above, what's stated on the label, along with inconsistent or absent screening for contaminants.

He mentions he chose this particular brand because of positive reviews on a forum dedicated to anxiety management, not because of any lab-testing certificate or third-party verification, and hadn't previously considered that a product's popularity online says nothing about whether its label accurately reflects what's actually in the bottle.

He also volunteers that he's never mentioned the CBD use to any physician before today, assuming it wasn't relevant since it's sold openly and doesn't require a prescription — a gap in disclosure the team notes is common with supplement use generally, and worth normalizing as something to always ask about directly rather than wait for patients to bring up.

Ben H. · 27 Self-treating with OTC CBD
History
Mild-moderate GAD; previously tried hydroxyzine, stopped for sedation
Current regimen
Over-the-counter CBD tincture x3 months, unmeasured/estimated dose
Reported effect
Subjective partial benefit, no sedation
Patient request
Wants to continue OTC CBD instead of starting a prescription medication

An unregulated product against an evidence-based alternative

Clinical Pharmacologist Opening

The honest answer is that CBD's anxiolytic evidence is real but genuinely mixed, and most of the positive trial data used doses well above what over-the-counter tinctures typically contain — he may be getting a placebo-adjacent dose, a therapeutic one, or something in between, and there's no reliable way to know from an unregulated product.

Primary Care Physician Response

The bigger practical problem isn't just underdosing, it's that independent testing of over-the-counter CBD products has repeatedly found real mislabeling — some products test far below stated potency, others above, and contaminant screening is inconsistent across brands. He's not choosing between a known dose of CBD and a prescription option; he's choosing an unknown quantity of an inconsistently regulated product.

Psychiatrist Final

I don't want to dismiss that he feels it's helping — that's real and worth taking seriously, not just as placebo. But for his level of symptom severity, an SSRI has a far deeper, more consistent evidence base and known, standardized dosing. My recommendation is to offer an SSRI trial while being honest that if he wants to continue CBD alongside it, or instead of it, that's his informed choice to make once he understands the regulatory gap clearly.

If he does run the two together, one more thing belongs in that informed choice: CBD inhibits CYP2C19 and CYP3A4, and can raise SSRI concentrations. The effect is best documented for citalopram and escitalopram, where added CBD measurably increased plasma levels; the in vitro signal for sertraline is weaker, but a case of hyponatremia and cognitive change after CBD was added to stable sertraline has been reported. Combined with an unverified product potency, that argues for watching for the usual dose-related SSRI effects rather than assuming a supplement can't move a prescription drug's levels.

Regimen selected
Sertraline — Offered
SSRI · Discussed as the evidence-based alternative
Presented as the more consistently evidenced, standardized-dose option given his GAD severity; his choice whether to start it.
Continued OTC CBD — His Informed Choice
Unregulated supplement · Not prescribed, not discouraged outright
Genuinely mixed efficacy evidence and real product-quality/labeling concerns discussed explicitly; decision left to him once informed.
Where this was left

Agreed: the regulatory and evidence gaps around over-the-counter CBD were explained directly. Ben elected to try an SSRI trial while deciding separately whether to continue the CBD tincture alongside it, understanding neither the dose nor the product's actual content is verified.

Educational content only — a composite teaching case, not a real patient encounter or a substitute for clinical guidance. About These Cases →