Drug Detail:Citalopram (Citalopram [ si-tal-o-pram ])
Drug Class: Selective serotonin reuptake inhibitors
1. How it works
- Citalopram is a medicine that may be used in the treatment of depression and other mood disorders.
- Experts are unsure exactly how citalopram works, although historically it was believed that citalopram's effects were due to its ability to rebalance chemicals in the brain, such as serotonin, that were thought to be imbalanced in people with anxiety, depression, and other mood disorders. Studies confirm that citalopram is still effective for treating mood disorders, such as depression, even though the way it works is unknown.
- The activity of citalopram against other neurotransmitters, such as norepinephrine or dopamine, is much less potent than other antidepressants.
- Citalopram belongs to a group of medicines called Selective Serotonin Reuptake Inhibitors (SSRIs).
2. Upsides
- May be used for the treatment of moderate-to-severe depression (also called Major Depressive Disorder).
- Less likely to cause drowsiness than some other antidepressants.
- Has also been used off-label for other conditions such as agitation associated with dementia, generalized and social anxiety disorder, alcoholism, eating disorders (such as binge-eating disorder), fibromyalgia, panic disorder, obsessive-compulsive disorder (OCD), and post-traumatic stress disorder (PTSD).
- Data from a limited number of trials suggest citalopram may be beneficial for premature ejaculation and premenstrual dysphoric disorder (off-label use).
- Research from two trials also supports its use for vasomotor symptoms associated with menopause (off-label).
- FDA approved for use in adults; however, some studies have investigated its use in children over the age of 7 years at dosage ranges of 10 to 40 mg/day.
- SSRIs in general, are better tolerated than many other medicines used for the treatment of depression.
- May be administered with or without food.
- Generic citalopram is available.
3. Downsides
If you are between the ages of 18 and 60, take no other medication or have no other medical conditions, side effects you are more likely to experience include:
- Insomnia, dry mouth, drowsiness, nausea, increased sweating, and sexual dysfunction. Side effects may be more likely with citalopram compared to escitalopram, a related drug.
- May increase the risk of suicidal thoughts or behavior in young adults (similar to other antidepressants).
- Interaction or overdosage may cause serotonin syndrome (symptoms include agitation, hallucinations, fast heart rate, dizziness, muscle tremor, nausea, vomiting, diarrhea).
- May cause a discontinuation syndrome if abruptly stopped or interrupted (symptoms include nausea, vomiting, diarrhea, headaches, sweating, tremors, vivid dreams, insomnia).
- May impair your judgment and affect your ability to drive or operate machinery. Alcohol should be avoided.
- May increase the risk of bleeding, especially if used with other drugs that also increase bleeding risk.
- May precipitate a manic episode in people with undiagnosed bipolar disorder.
- May cause lowering of total body sodium (called hyponatremia); elderly people or people taking diuretics or already dehydrated may be more at risk.
- May interact with several other drugs including those metabolized by hepatic enzymes CYP 3A4 and 2C19, other antidepressants, and medicines that also cause serotonin release (such as tramadol, St John's wort, and opioids). Should not be given concurrently or within 14 days of a monoamine oxidase inhibitor.
- May cause prolongation of the QT-interval especially when used in conjunction with other QT prolonging medications. Due to the risk of QT-prolongation, the maximum recommended dose is 40 mg/day. People over the age of 60 years, those with significant liver disease, or those on certain interacting medications (such as cimetidine or omeprazole) should not take more than 20 mg/day.
- A lower dosage of 10 mg/day may be needed in people who are sensitive to overstimulation effects such as anxiety or insomnia.
- Rarely causes seizures.
- Complications, such as prolonged hospitalization, respiratory support, and tube feeding, have been reported in neonates exposed to citalopram during the third trimester of pregnancy. Weigh up the potential benefits versus the risks in women exposed to citalopram during the third trimester. Citalopram is excreted into breastmilk and there have been reports of drowsiness, decreased feeding, and weight loss reported in the breastfeeding infant.
Note: In general, seniors or children, people with certain medical conditions (such as liver or kidney problems, heart disease, diabetes, seizures) or people who take other medications are more at risk of developing a wider range of side effects. View complete list of side effects
4. Tips
- May be taken with or without food.
- Blood tests may need to be taken before treatment to check electrolyte levels (for example potassium, magnesium) and these corrected if necessary before treatment begins.
- Dosages greater than 40mg/day are not recommended.
- Report to your doctor any signs of worsening depression or suicidal thoughts particularly during the first few months of therapy.
- Do not stop suddenly as withdrawal symptoms may occur; taper off slowly under medical supervision.
- Do not drive or operate machinery until the full effects of citalopram are known as it may impair your judgment and affect your ability to drive or operate machinery.
- Report any problems with bleeding or bruising to your doctor, also report any unexplained skin changes (such as blisters or rashes), problems with urination, eye pain or swelling, and vision changes to your doctor.
- Seek urgent medical advice if symptoms consistent with serotonin syndrome (such as agitation, hallucinations, fast heart rate, dizziness, flushing, nausea, diarrhea) develop.
- Tell your doctor if you are pregnant or you become pregnant while taking citalopram. Complications, such as prolonged hospitalization, respiratory support, and tube feeding, have been reported in neonates exposed to Citalopram during the third trimester of pregnancy. Citalopram is also excreted into breastmilk and there have been reports of drowsiness, decreased feeding, and weight loss in the breastfeeding infant.
5. Response and effectiveness
- Peak blood levels of citalopram occur within 1 to 6 hours, with an average time of 4 hours.
- Initial improvements may be seen within 1 to 2 weeks; however, it may take up to 4-6 weeks of regular dosing before the maximum antidepressant effects are seen.
- Initial effects for anxiety disorders (such as generalized anxiety, OCD, panic disorder, and posttraumatic stress disorder) may be observed within two weeks with continued improvements seen after four to six weeks.
- Effects of citalopram last one to two days after a single dose. The half-life is 24 to 48 hours (average 35 hours). Half-life doubles with liver disease and increases by 30% to 50% in patients over the age of 60 years.
6. Interactions
Medicines that interact with citalopram may either decrease its effect, affect how long it works, increase side effects, or have less of an effect when taken with citalopram. An interaction between two medications does not always mean that you must stop taking one of the medications; however, sometimes it does. Speak to your doctor about how drug interactions should be managed.
Common medications that may interact with citalopram include:
- anticoagulants (blood thinners), such as warfarin, or other drugs that have blood-thinning effects such as aspirin or NSAIDs
- anticonvulsants, such as phenytoin, phenobarbital, or primidone
- antipsychotics (such as butyrophenones, phenothiazines, or thioxanthenes) and atypical antipsychotics (eg, olanzapine, quetiapine, ziprasidone)
- any medication that may cause drowsiness, such as benzodiazepines (eg, diazepam, lorazepam), first-generation antihistamines (such as doxylamine or promethazine), metoclopramide, or opioids (such as codeine, morphine)
- bupropion
- duloxetine
- herbs with bleeding as a side effect, such as anise, alfalfa, or bilberry
- hydroxychloroquine
- lithium
- medications that may affect the heartbeat by prolonging the QT interval, such as amiodarone, encainide, or flecainide
- pimozide
- other antidepressants, such as tricyclic antidepressants (eg, amitriptyline), monoamine oxidase inhibitors (eg, isocarboxazid, phenelzine, and tranylcypromine), and SSRIs (eg, paroxetine, sertraline)
- other medications that affect serotonin, such as amphetamines, fentanyl, lithium, tramadol, triptans (eg, almotriptan, eletriptan, or sumatriptan), or St. John's Wort
- other medications that are metabolized by the same enzymes (CYP2C19 or CYP3A4)
- others, such as HIV medications (fosamprenavir, ritonavir)
- voriconazole.
Avoid drinking alcohol or taking illegal or recreational drugs while taking citalopram.
Note that this list is not all-inclusive and includes only common medications that may interact with citalopram. You should refer to the prescribing information for citalopram for a complete list of interactions.