Citalopram (Celexa) is one of the most widely prescribed antidepressants and antianxiety medications. It belongs to the group of antidepressants called selective serotonin reuptake inhibitors. It works by helping to restore the balance of the neurotransmitter serotonin in the brain. Neurotransmitters are naturally occurring chemicals in the body, which relay messages from one nerve cell to another. Among the SSRIs, citalopram was a late addition to the US market when it received approval for the treatment of major depressive disorder in 1998.
Citalopram is well absorbed orally, and absorption is unaffected by food. The starting daily dosages are 10 to 20 mg for citalopram. For some patients, daily dosages of 20 mg are sufficient, although higher dosages may be required in some others.
Uses of Citalopram
Citalopram is a first-line agent for pharmacological treatment of significant OCD, anxiety disorders, and mood symptoms. It is also used to treat panic disorder, PTSD, fibromyalgia, and neuropathic pain.
- Depression or Major depressive disorder (MDD): Usual adult initial dose is 20 mg orally once a day, the maintenance dose is 20 to 40 mg orally once a day, and maximum dose is 40 mg orally per day. The initial dose may be increased if necessary to 40 mg once a day after at least 1 week of therapy. Doses of 60 mg/day do not have an advantage in efficacy over 40 mg/day doses. Acute episodes of depression may require several months or more of sustained pharmacologic therapy. The recommended dose for depression in those over 60 years is 20 mg orally once a day. Citalopram has been associated with dose-dependent prolongation of the QT interval on EKG and, as a result, it is recommended not to exceed 20 mg/day of citalopram in persons aged 60 years or older. It is not recommended for treating depression in children under 18, in whom efficacy is doubtful and adverse effects, including excitement, insomnia, and aggression in the first few weeks of treatment may occur. The possibility of increased suicidal ideation is a concern in this age group.
- Anxiety disorders: Citalopram is effective in the treatment of generalized anxiety disorder, phobias, social anxiety disorder (reduce the activation of amygdala and hippocampus), post-traumatic stress disorder and obsessive-compulsive disorder. A lower side-effect profile favors its use. It has the additional advantage of reducing depression, which is not uncommonly associated with anxiety. Its effects are slow in onset (>2 weeks). If started at too high a dose, it may initially exacerbate symptoms of anxiety and, therefore, in older adults with anxiety disorders, initial dose is 5 mg/day, target dose is 10 mg/day, and maximum dose is 20 mg/day. An added advantage of citalopram use in the elderly is its low propensity for drug interactions and short half-life.
- Generalized anxiety disorders (GAD): Large RCTs, as well as systematic reviews and meta-analyses, confirm citalopram, along with other SSRIs, is first-line choice. It is useful in the treatment of adults, children, and elderly patients with GAD. Data suggest the continued efficacy of citalopram for GAD after 24 weeks of treatment, with an additional 20 percent of patients responding in the second 12 weeks. The medication dosages used to treat individuals with GAD are similar to those used to treat major depressive disorder.
- Obsessive-compulsive disorder (OCD): Citalopram is efficacious for the treatment of OCD in adults and children, though it is not FDA-approved for this purpose. A full response to treatment may take longer than is the case in depressive disorders. Intravenous administration of citalopram has been studied as a treatment for OCD. Among patients with moderate to severe OCD who had failed at least two adequate treatment trials of SSRIs, excluding citalopram, about 60 percent of patients had a significant decrease in OCD symptoms after 3 weeks of intravenous citalopram. Dose ranges for pediatric OCD are 10–60 mg/day.
- Panic Disorder (PD): There is currently evidence that citalopram is effective in the acute treatment of PD. Citalopram and also other SSRIs are often recommended as initial therapy. Several smaller placebo-controlled trials and one large multicenter placebo-controlled acute trial have been published demonstrating that citalopram is an effective treatment of PD. It is effective for panic disorder in older adults.
- Fibromyalgia: Fibromyalgia is a chronic disorder characterized by widespread musculoskeletal pain, fatigue, and insomnia. Its cause is unknown. Citalopram is effective in its treatment.
- Agitation in dementia: Citalopram showed efficacy for agitation in Alzheimer’s disease in a randomized clinical trial. It demonstrated reductions in agitation, aggression and caregiver distress in dementia patients; however, treatment was also associated with a worsening of cognition and prolongation of the QTc interval on the EKG.
- Depression post-stroke or post-TBI: citalopram (20 mg/day under age 65; 10 mg/day over age 65), a significantly greater reduction in Hamilton Depression Scores over 6 weeks was observed. It is also safe and well-tolerated in individuals with TBI.
- Premenstrual dysphoric disorder (PMDD): Citalopram is the preferred SSRI for mood disorders in PMDD.
- Body dysmorphic disorder (BDD): Effective doses needed to treat BDD successfully appear often to be substantially higher than those typically needed to treat many other disorders, such as depression. The recent dosing limit for citalopram makes it a less appealing option.
- Alcohol and drug abuse: Another SSRI whose effects on alcohol consumption have been extensively examined is citalopram. Citalopram and sertraline may be of value in subgroups of heavy drinkers, particularly those with a later onset of problem drinking. Citalopram combined with CBT and contingency management reduces cocaine use.
- Citalopram is useful in the treatment of premature ejaculation.
- Some studies found that paraphilic patients with comorbid depression showed a concurrent decrease in paraphilic behavior when their depressive symptoms improved with citalopram.
- Citalopram reduced the frequency of sex addicts’ symptomatic sexual urges, masturbation, and use of pornography while having no significant effect on partnered sexual behaviors.
- Mild/Moderate PMS: Citalopram 5–20 mg daily.
- Cancer-related fatigue: Citalopram in starting dose of 10–20 mg/day, with a dose range of 10-40 mg/day works well.
- Trichotillomania (TTM, hair-pulling disorder): Citalopram used for the treatment of TTM suggests positive treatment response with short-term and long-term benefits. It is first-line choice of medication for TTM.
- Psychocutaneous disorders: Citalopram is a first-line treatment in psychocutaneous disorders like body-focused repetitive behaviors, pruritus, cutaneous dysesthesias, such as glossodynia, vulvodynia, trichodynia/scalp dysesthesia urogenital and rectal pain syndrome.
- Citalopram can be effective for middle-aged and older adults with schizophrenia and subsyndromal depression.
- Transplant patients: Citalopram is preferred because of its lack of drug-drug interactions.
Dosage of Citalopram (Celexa)
Citalopram is available in 10-, 20-, and 40-mg-size tablets. The 20- and 40-mg-size tablets are scored. Citalopram is also available in an oral solution at a concentration of 10 mg/5 mL.
Many patients are observed to do well if citalopram is taken after meals for the first few days. After that period, they can take the medication with or without food.
The recommended starting dose for citalopram is 20 mg/day, with the expectation of generally increasing the dose to 40 mg/day, which is typically done after at least 1 week on the initial dosing. Highly anxious patients or those with increased sensitivities to side effects of medications may benefit from starting with the 10-mg tablet. Citalopram therapeutic range is 10-40 mg/day. The maximum recommended dose of citalopram is 20 mg per day for patients older than 60 years of age.
For children, adolescents, the elderly, and patients who find medications generally difficult to tolerate, 50% reductions in these doses are reasonable starting doses. For citalopram, the initial doses should be maintained for 1–2 weeks, after which they can be increased in 10 or 20 mg increments to a dose of 40 mg/day if there is no response. Citalopram is currently limited by the aforementioned concerns about cardiac toxicity, with an upper limit of 40 mg/day in adults and 20 mg/day in those older than 65 years, as recommended by the FDA.
Side Effects of Celexa (Citalopram)
Common citalopram side effects may include:
- Problems with memory or concentration
- Gastrointestinal distress
- Dry mouth, increased sweating
- Increased appetite
- Changes in weight
- Decrease in libido
- Difficulty having an orgasm
Less common side effects of Celexa include:
- Blurred vision
- Suicidality – suicidal thoughts and planning as well as unsuccessful attempts
- Increase in the frequency or amount of urination
- Lack of emotion
- Menstrual changes
- Skin rash or itching
- Trouble breathing
Use in Pregnancy and Breastfeeding
Citalopram did not significantly increase the risk for most birth defects. It may lead to pulmonary hypertension in the newborn. However, safety is uncertain in pregnancy – fluoxetine is a better alternative.
Citalopram does not affect hepatic metabolizing enzymes and may be less likely to cause drug interactions. Citalopram, escitalopram, and sertraline seem to have the fewest drug-drug interactions.
Its serum concentrations are decreased by carbamazepine.
Citalopram may reduce dopamine turnover, and use in combination with dopamine-receptor antagonists can raise prolactin levels, even causing breast enlargement and galactorrhea and produce extrapyramidal side effects.
It has interactions with cimetidine, lithium, and St. John’s wort.
Concurrent administration of an SSRI with an MAOI, L-tryptophan, or lithium can result in risk of serotonin syndrome. Its symptoms in order of appearance as the condition worsens are (1) diarrhea; (2) restlessness; (3) extreme agitation, hyperreflexia, and autonomic instability with possible rapid fluctuations in vital signs; (4) myoclonus, seizures, hyperthermia, uncontrollable shivering, and rigidity; (5) delirium, coma, status epilepticus, cardiovascular collapse, and death.
Accordingly, with the exception of fluoxetine, SSRIs like citalopram should not be administered within 14 days of discontinuing treatment with an MAOI. At least 14 days should pass before an SSRI (again, with the exception of fluoxetine) is started after treatment with an MAOI is stopped.
Citalopram enjoys a lower degree of protein binding (80 percent) than many other SSRIs. Thus, protein-binding interactions would not appear to be a problem with citalopram. The combination of citalopram with a highly protein-bound drug, such as warfarin, resulted in a prolongation of prothrombin time by only 5 percent.
Coadministration of citalopram (40 mg/day) for 22 days resulted in a doubling of the plasma levels of metoprolol (Lopressor).
Coadministration of citalopram (40 mg per day) for 10 days along with a single dose of imipramine (Tofranil) (100 mg) did not alter the plasma concentrations of imipramine but did increase plasma levels of the primary metabolite, desipramine (Norpramin), by 50 percent.
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