Citalopram (Celexa)

What it treats

Citalopram is approved by the U.S. Food and Drug Administration to treat major depressive disorder. Prescribers also use it for anxiety conditions, which is an off-label use, meaning a purpose the label doesn't formally list even though evidence and practice support it.

It is worth knowing that escitalopram, sold as Lexapro, is a closely related, refined version of citalopram. Citalopram is a mix of two mirror-image forms of the same molecule, and escitalopram is just the active one of the two. The two drugs are similar, and a prescriber may choose between them based on dosing, side effects, and cost.

How it works

Citalopram is a selective serotonin reuptake inhibitor, usually shortened to SSRI. Nerve cells in the brain pass messages using chemical messengers, and serotonin is one of them. After a cell releases serotonin, it normally reabsorbs much of it, a process called reuptake. Citalopram slows that reabsorption, so more serotonin stays available between cells.

How that eases depression and anxiety isn't fully understood. The popular "chemical imbalance" explanation is an oversimplification, and it's worth being honest about that. What is clear is that the early change in serotonin signaling sets off slower adjustments in the brain over the following weeks. Those slower changes are thought to do the real work, which is part of why the medication takes time rather than working the day you start it.

What to expect

Common side effects

Most people get some side effects. The common ones include:

• Nausea.
• Dry mouth.
• Drowsiness, or for some people, trouble sleeping.
• Increased sweating.
• Fatigue.
• Dizziness.
• Sexual side effects.

Many of the stomach-related effects ease within one to two weeks. Taking the dose with food often helps with nausea. Sweating and sexual side effects tend to last as long as the medication is taken rather than fading. If a side effect is severe, or it isn't improving after a few weeks, that's a conversation to have with the prescriber rather than a reason to stop on your own.

Serious side effects and warnings

Serious problems are uncommon, but a few are worth knowing.

Boxed warning. Like all antidepressants, citalopram carries an FDA boxed warning that it can increase suicidal thoughts and behaviors in children, teenagers, and young adults under 25, especially in the first weeks of treatment or after a dose change. This does not mean the medication harms most people. It means the early period deserves close attention, and that any worsening of mood, agitation, or new thoughts of self-harm should prompt contact with the prescriber promptly.

• Heart rhythm and the QT interval. Citalopram has a dose-related effect on the QT interval, a measure of the timing of the heart's electrical cycle. A longer QT interval can, rarely, lead to an abnormal heartbeat. Because of this, the FDA sets dose limits. The general maximum is 40 mg a day. The maximum is 20 mg a day for adults over 60, for people with significant liver impairment, and for some others. Citalopram should be used with caution alongside other medicines that also affect the QT interval.
• Serotonin syndrome. A rare reaction caused by too much serotonin activity, most likely when citalopram is combined with other drugs that raise serotonin. Signs include agitation, a fast heartbeat, high body temperature, shivering, muscle twitching, and confusion. It is a medical emergency.
• Increased bleeding risk. Citalopram can make bleeding and bruising more likely, especially alongside NSAIDs such as ibuprofen or naproxen, aspirin, or blood thinners.
• Low sodium. A drop in blood sodium can happen, more often in older adults. Symptoms can include headache, confusion, and weakness.
• Mood switch in bipolar disorder. In people who have bipolar disorder, an antidepressant can sometimes trigger a manic or agitated state, which is one reason an accurate diagnosis matters.

Sexual side effects

Citalopram, like other SSRIs, commonly affects sexual function, and it deserves a direct answer rather than a footnote. It can lower sex drive, delay orgasm or make it hard to reach, and cause arousal or erection difficulties. Estimates vary widely depending on how the question is asked, but by many measures a third or more of people notice some change.

These effects usually last as long as the medication is taken, rather than fading like nausea does. They are worth raising with a prescriber, because there are real options: lowering the dose, switching to a medication less likely to cause this, such as bupropion, or adding another medication to counter it. A small number of people report sexual side effects that continue after stopping the drug. This is uncommon and not well understood, but it is a real phenomenon and worth knowing about before you start.

Weight, appetite, and sleep

Citalopram is fairly weight-neutral in the short term. With long-term use, modest weight gain is possible for some people, though it tends to be smaller than with a few other antidepressants.

Its effect on sleep goes both ways. It makes some people drowsy and makes others restless or wakeful. Because of this split, the time of day to take it is often chosen based on how it affects a given person. If it causes drowsiness, a prescriber may suggest taking it at night. If it disturbs sleep, the morning may suit better.

Starting and dosing basics

This section is general background, not a dosing instruction for any individual. The right dose is a decision for a prescriber.

Citalopram comes as tablets and as an oral solution. A common starting dose is 20 mg a day. The dose may be raised gradually based on how a person responds and tolerates it. Because of the dose-related QT effect, the general maximum is 40 mg a day. The maximum is 20 mg a day for adults over 60 and for people with significant liver impairment. It can be taken with or without food, though food helps with nausea.

Missed doses and interactions

If you miss a dose, the general guidance is to take it when you remember, unless it is almost time for the next dose. In that case, skip the missed dose and carry on. Don't take two doses to make up for one.

Several interactions matter. Citalopram must not be combined with MAOI antidepressants, and a gap is needed when switching between them. It should not be taken with pimozide. Combining it with other drugs that raise serotonin, such as triptans for migraine, tramadol, other antidepressants, or the supplement St. John's wort, increases the risk of serotonin syndrome. Medicines that affect the QT interval add to citalopram's own effect on heart rhythm. NSAIDs and blood thinners add to bleeding risk.

Alcohol is not formally prohibited, but it isn't recommended. It can worsen side effects, disturb sleep, and work against the mood benefit you're taking the medication for. Give every prescriber and pharmacist a full list of your medications and supplements, including over-the-counter ones.

Stopping and tapering

Citalopram is not addictive in the usual sense of that word. It does not cause cravings or compulsive use. But the body does adjust to it, and stopping suddenly can cause discontinuation symptoms: dizziness, flu-like feelings, irritability, vivid dreams, trouble sleeping, and the brief electrical "brain zap" sensations many people describe.

These symptoms are uncomfortable but not dangerous, and they are more likely the higher the dose and the longer the medication has been taken. The way to avoid them is a gradual taper planned with a prescriber, stepping the dose down over weeks. Deciding to stop because you feel better is understandable, and sometimes it is the right call, but it is still worth doing slowly and with guidance.

Pregnancy and breastfeeding

This is an area where individual circumstances matter and the decision belongs with a clinician. Untreated depression and anxiety carry their own risks during pregnancy. Citalopram passes into breast milk in low amounts. None of that adds up to one answer that fits everyone. Anyone who is pregnant, planning a pregnancy, or breastfeeding should talk it through with their prescriber so the specific risks and benefits can be weighed for their situation.

Cost and generic availability

Citalopram has been available as a generic for many years and is inexpensive. The brand name Celexa and generic citalopram contain the same active medication and work the same way. Most insurance plans cover it, and for people paying out of pocket, generic citalopram is among the lower-cost antidepressants.

Common questions

How long until citalopram works? Some early effects on sleep and appetite can show within one to two weeks. The fuller effect on mood usually takes four to six weeks, sometimes up to eight.

Is citalopram addictive? No, not in the usual sense. It doesn't cause cravings or compulsive use. The body does adapt to it, which is why stopping should be gradual.

How is it different from escitalopram (Lexapro)? Escitalopram is a refined version of citalopram, containing only the active half of the molecule. The two are closely related and similar in effect. A prescriber may choose between them based on dosing, side effects, and cost.

Can I drink alcohol while taking it? It isn't banned, but it isn't recommended. Alcohol can worsen side effects and sleep and can undercut the benefit.

Should I take it in the morning or at night? Either can work. Because citalopram makes some people drowsy and others wakeful, the timing is often chosen based on how it affects you. Your prescriber can help you decide.

Questions to ask your prescriber

• What are we hoping this treats, and how will we know it's working?
• Given the dose limits tied to heart rhythm, what is the right maximum dose for me?
• Which side effects should I expect early, and which ones should I call about?
• How long should I plan to take it?
• If we decide to stop it later, how would we do that safely?

Sources

This guide draws on current prescribing information and public health references. It is reviewed for clinical accuracy and updated as guidance changes.

• U.S. Food and Drug Administration. Citalopram hydrobromide (Celexa) prescribing information.
• MedlinePlus, U.S. National Library of Medicine. Citalopram.
• National Institute of Mental Health. Mental health medications.
• American Psychiatric Association. Practice guideline for the treatment of patients with major depressive disorder.