Citalopram

• Depression
• Panic disorder, with or without agoraphobia
• Generalised anxiety, off-label
• Obsessive compulsive disorder, off-label

Escitalopram is the closely related refinement of the same molecule, used at roughly half the dose and with its own, lower, ceiling.

• Usually started at 10 to 20mg once daily
• Maximum 40mg daily for adults under 65
• Maximum 20mg daily if you are over 65, or have liver impairment
• Morning or evening, with or without food — whichever suits your sleep

What to expect

Little in the first two weeks, some improvement by four, fuller effect by six to eight. The first fortnight is frequently the worst part — more anxious, more restless, poorer sleep — and that is when most people stop.

Knowing that in advance is the single biggest predictor of getting through it.

Never stop it abruptly. Coming off needs a gradual taper.

• Other QT-prolonging drugs — the interaction that defines citalopram's safety profile
• NSAIDs such as naproxen, aspirin, warfarin and DOACs — increased bleeding risk. Stomach protection is often added
• Triptans, tramadol, St John's wort, lithium — serotonin syndrome risk
• Diuretics — additive risk of low sodium
• Cimetidine and omeprazole raise citalopram levels

Monitoring

• An ECG before starting in anyone with cardiac disease, on other QT-prolonging drugs, or with electrolyte abnormalities
• Sodium in older people, particularly in the first weeks
• Review within one to two weeks in anyone under 25, and early review for everyone
• Thyroid function before starting, since an underactive thyroid mimics depression

Citalopram is a very cheap generic. On a private prescription the drug cost plus dispensing fee is usually less than the England NHS prescription charge. NHS prescriptions are free in Wales.

What is worth more than the tablet

Therapy — and the best version is free. NHS Talking Therapies takes self-referrals without a GP appointment, and CBT has strong evidence in both depression and anxiety.

We would rather point you there than sell you something. Private therapy is worth paying for when local NHS waits are long or you need a specific modality.

Where not to spend

• Pharmacogenomic testing to “choose your antidepressant” — heavily marketed, weak evidence that it improves real-world outcomes
• Mood supplements. St John's wort in particular interacts dangerously with SSRIs

Citalopram is not addictive — no craving, no dose escalation — but stopping abruptly causes discontinuation symptoms: dizziness, “brain zaps”, nausea, irritability, vivid dreams and flu-like aching.

Those are frequently mistaken for the original illness returning, which matters because it changes what you do next.

Coming off

• Not before six months of feeling well, and usually longer after a first episode
• Reduce gradually over weeks to months, going slower at the lower doses
• Come off during a settled period, not a crisis
• If symptoms are difficult, go back up a step and reduce more slowly — that is how tapering is meant to work, not a failure

Switching

Between SSRIs this is usually straightforward. Moving to or from certain other antidepressants needs a washout to avoid serotonin syndrome, and should never be improvised.

Alternatives

• Sertraline — no comparable dose ceiling, often preferred where higher doses may be needed
• Fluoxetine — long half-life, gentler discontinuation
• Escitalopram — the refined version, at roughly half the dose
• Mirtazapine — where sleep and appetite are the problem
• Talking therapy alone — a legitimate first choice in mild to moderate depression

Why is there a maximum dose?

Because citalopram prolongs the QT interval on the ECG in proportion to the dose, and that can cause dangerous heart rhythms.

40mg is the ceiling for adults under 65; 20mg over 65 or with liver problems. This followed a 2011 safety review and the limits are firm.

How is it different from sertraline?

They are similarly effective. The practical difference is the dose ceiling — sertraline has more headroom, which matters if you need a higher dose. Sertraline is also generally preferred in older people and in heart disease.

How long before it works?

Four to six weeks for a proper effect. The first two weeks can feel worse, and that is when most people stop.

Is it addictive?

No. There is no craving and no need for increasing doses. It does cause discontinuation symptoms if stopped suddenly, which is a different thing entirely and the reason it is tapered.

What about sexual side effects?

Common, under-discussed, and worth raising. Reduced desire, delayed orgasm and erectile difficulty all occur, and usually improve on a lower dose or a different drug.

Can I drink alcohol?

Small amounts are usually tolerated, but alcohol works against the treatment — it is a depressant, it worsens sleep, and it amplifies drowsiness.

I feel dizzy and unsteady since starting. Is that important?

Worth reporting, particularly if you are older. SSRIs can lower sodium, most often in the first weeks, and that causes confusion, unsteadiness and drowsiness. It is checked with a simple blood test.