Citalopram is an SSRI antidepressant used for depression, anxiety, panic disorder and OCD. It takes several weeks to work, and it must not be stopped abruptly. It has a dose ceiling that other SSRIs do not, because of an effect on heart rhythm.
What is Citalopram?
Citalopram is a selective serotonin reuptake inhibitor (SSRI), dispensed as 10 mg, 20 mg and 40 mg tablets. It is a Schedule 5 medicine, sold under its own name and as Adco-Talomil, Depramil, Cipramil and Tamomilt.
Serotonin is a signalling chemical released between nerve cells. After it has acted, most is reabsorbed by the cell that released it. Citalopram blocks that reuptake, so more serotonin stays available in the synapse.
“Selective” means it acts mainly on serotonin, largely leaving other systems alone — which is why SSRIs are better tolerated than older antidepressants such as amitriptyline, and considerably safer in overdose.
Two things are worth knowing up front.
It takes weeks, not days. Serotonin levels rise within hours, but the clinical benefit takes two to six weeks, and sometimes longer. The delay is thought to reflect gradual adaptation in receptors and downstream changes rather than the serotonin level itself. Stopping at two weeks because nothing has happened is the commonest reason people conclude an antidepressant failed.
Citalopram has a dose ceiling other SSRIs lack. It prolongs the QT interval — an aspect of the heart’s electrical cycle — in a dose-dependent way, and regulators have set maximum amounts, lower again in people over 65 and in liver impairment. That is why your prescriber may not simply increase it if it is not working, and may switch instead.
Escitalopram is the closely related, purified form of citalopram, often used similarly.
What is Citalopram commonly used for?
- Depression, its main licensed use.
- Panic disorder, with or without agoraphobia.
- Generalised anxiety disorder.
- Obsessive-compulsive disorder.
- Social anxiety disorder.
- Post-traumatic stress disorder, in some circumstances.
- Premenstrual dysphoric disorder.
In anxiety, expect an early worsening. SSRIs commonly increase anxiety, restlessness or agitation in the first one to two weeks before improving. That is well recognised, it is usually managed by starting at a lower amount and increasing slowly, and it settles. Knowing it may happen makes it far less alarming — and it is a reason to stay in contact with your prescriber early on rather than stopping.
Medication is one part of treatment. Talking therapy, particularly cognitive behavioural therapy, has strong evidence in depression and anxiety, and the combination generally works better than either alone. Sleep, activity, alcohol and social contact all matter materially.
How Citalopram fits into this medicine category
| Group | Examples | Role |
|---|---|---|
| SSRIs | Citalopram, escitalopram, sertraline, fluoxetine | First-line depression and anxiety |
| SNRIs | Venlafaxine, duloxetine | Depression, anxiety; duloxetine also nerve pain |
| Tricyclics | Amitriptyline (Trepiline) | Nerve pain, migraine prevention; depression at higher amounts |
| Benzodiazepines | Clobazam (Urbanol), alprazolam (Xanax) | Short-term anxiety only; dependence |
| Antipsychotics | Quetiapine (Quesara) | Add-on in depression; bipolar disorder |
Benzodiazepines relieve anxiety within an hour but cause dependence; an SSRI takes weeks and does not. That difference is the whole reason SSRIs are first-line. See the mental health and neurology medicines hub.
What to check before using Citalopram
Take it at the same time each day, with or without food. Morning suits most people; if it makes you drowsy, evening may suit better.
Do not stop abruptly. Discontinuation symptoms are common with SSRIs — dizziness, electric-shock sensations, nausea, irritability, vivid dreams and flu-like feelings. They are not dangerous but can be unpleasant, and they are avoided by tapering over weeks under medical guidance.
Tell your prescriber or pharmacist if you:
- Have a heart rhythm problem, a long QT interval, or a family history of sudden cardiac death. This matters more with citalopram than with most SSRIs.
- Have low potassium or magnesium, which compounds the QT effect.
- Have bipolar disorder, where an antidepressant alone can trigger a switch to mania.
- Have epilepsy, liver or kidney disease, or glaucoma.
- Have a history of bleeding, or take warfarin, aspirin or an anti-inflammatory — SSRIs affect platelets and increase bleeding risk, particularly stomach bleeding when combined with an NSAID.
- Take tramadol, a triptan, lithium, St John’s wort, or another serotonergic medicine — the combination risks serotonin syndrome.
- Take an MAOI, which must not be combined.
- Are pregnant, planning pregnancy or breastfeeding.
- Are over 65, where the dose ceiling is lower.
Follow the dispensing label exactly. This page does not set doses.
Possible cautions and when to ask a pharmacist or doctor
Watch mood closely in the first weeks. Anyone starting an antidepressant, particularly under 25, should be monitored for worsening mood, agitation, restlessness or thoughts of self-harm early on. This is a recognised early risk. Report it promptly — it does not mean the treatment is wrong, but it needs managing.
Give it a fair trial. Two to six weeks at a steady amount before judging it, and often longer for full benefit.
Common early effects — nausea, headache, disturbed sleep, dry mouth, sweating — usually settle within a couple of weeks.
Sexual side effects are common and under-discussed: reduced desire, difficulty reaching orgasm, erectile difficulty. They are reversible on stopping, and worth raising rather than silently enduring — dose changes and alternatives exist.
Low sodium (hyponatraemia) is a recognised effect, particularly in older adults. Report confusion, marked drowsiness, headache or unsteadiness.
Serotonin syndrome is an emergency: agitation, confusion, a racing heart, sweating, tremor, muscle twitching or rigidity, and fever — usually after starting or adding a serotonergic medicine.
Do not stop because you feel better. Treatment usually continues for at least six months after recovery to reduce relapse.
Seek urgent medical attention for thoughts of self-harm; agitation with fever, sweating and a racing heart; palpitations or fainting; a seizure; unusual bruising or bleeding, or black stools; or marked confusion.
Related medicine guides
Frequently asked questions
What is citalopram used for? Depression, panic disorder, generalised anxiety, OCD and social anxiety. It is an SSRI antidepressant.
How long before it works? Two to six weeks at a steady amount, sometimes longer. Stopping at two weeks is the commonest reason people think it failed.
Why did my anxiety get worse at first? SSRIs commonly increase anxiety or restlessness in the first week or two before improving. It is expected and usually settles — tell your prescriber rather than stopping.
Why is there a maximum dose? Citalopram prolongs the QT interval in a dose-dependent way, so maximum amounts are set — lower again over 65 and in liver impairment.
Can I stop taking it suddenly? No. Discontinuation symptoms such as dizziness and electric-shock sensations are common. Taper over weeks with medical guidance.
Will it affect my sex life? Sexual side effects are common with SSRIs and reversible on stopping. Raise it with your prescriber — dose changes and alternatives exist.