Serotonin is a brain chemical that carries nerve impulses from one nerve cell to another. Researchers think that depression and certain other mental disorders may be caused, in part, because there is not enough serotonin being released and transmitted in the brain. Like the other SSRI antidepressants, fluoxetine (Prozac), sertraline (Zoloft), and paroxetine (Paxil), citalopram increases the level of brain serotonin (also known as 5-HT). Increased serotonin levels in the brain may be beneficial in patients with obsessive-compulsive dirder, alcoholism, certain types of headaches, post-traumatic stress disorder (PTSD), premenstrual tension and mood swings, and panic disorder.
Citalopram is available in 20-mg, 40-mg, and 60-mg tablets.
Recommended dosage
The daily dosage of citalopram for depression ranges from 20–60 mg. The initial dosage is usually 20 mg per day. This dosage may then be increased to 40 mg per day at an interval of no less than one week. Most patients experience relief from depression at this dosage and do not require more than 40 mg per day. The dosage is taken once daily, either in the morning or in the evening.
Patients who are being treated for panic disorder receive doses ranging from 20–60 mg daily. A dosage of 20–30 mg daily appears to be optimal for the treatment of most panic disorders.
Precautions
Patients who are allergic to citalopram, any other SSRI drug, or any component of the preparation should not take citalopram.
Patients with liver problems and elderly patients (over age 65) need to take smaller amounts of the drug. Dosage for these patients should start at 20 mg but can be increased to 40 mg daily if needed. Patients with kidney problems do not need dosage adjustments. Patients with history of mania, suicide attempts, or seizure disorders should start citalopram with caution and only under close physician supervision. There is no clinical data available on the use of citalopram in children and adolescents.
Side effects
More than 15% of patients develop insomnia while taking citalopram. Nausea and dry mouth occur in about 20% patients being treated with citalopram. Patients also experience tremor, anxiety, agitation, yawning, headaches, dizziness, restlessness, and sedation with citalopram therapy. These side effects usually diminish or disappear with continued use of the drug, although it may take up to four weeks for this to occur.
A drop in blood pressure and increased heart rate have been associated with citalopram use. In general, patients do not experience weight gain or loss after starting citalopram.
Sexual dysfunction, which includes decreased sex drive in women and difficulty ejaculating in men, is also associated with the use of citalopram. In some patients, it may take up to 12 weeks for these side effects to disappear. In some patients these sexual side effects never resolve. If sexual side effects continue, the dose of citalopram may be reduced, patients can also have drug holidays where the weekend dose is either decreased or skipped, or they can discuss with their physician the risks and benefits of switching to another antidepressant.
Interactions
Citlopram interacts with a long list of other medications. Anyone starting this drug should review the other medications they are taking with their physician and pharmacist for possible interactions. Patients should always inform all their health care providers, including dentists, that they are taking citalopram.
Serious side effects called serotonin syndrome have resulted from the combination of antidepressants such as citalopram and members of another class of antidepressants known as monoamine oxidase (MAO) inhibitors. Serotonin syndrome usually consists of at least three of the following symptoms: diarrhea, fever, sweatiness, mood or behavior changes, overactive reflexes, fast heart rate, restlessness, shivering or shaking. Because of this, citalopram should never be taken in combination with MAO inhibitors. MAO inhibitors include isocarboxazid, nialamide, pargyline, selegiline, phenelzine, procarbazine, iproniazid, and clorgyline. Patient taking any MAO inhibitors, should stop the MAO inhibitor then wait at least 14 days before starting citalopram or any other antidepressant. The same holds true when discontinuing citalopram and starting an MAO inhibitor.
Buspirone, an anti-anxiety medication, should not be used together with citalopram. Ginkgo biloba and St. John's Wort, herbal supplements that are common in the United States, should not be taken together with citalopram.
BOOKS
Forest Pharmaceuticals, Inc. Staff. Product Information: Celexa (r), citalopram. St. Louis, MO: Forest Pharmaceuticals, Inc., 2001.
Lacy, Charles F. Drug Information Handbook. Lexi-Comp, Inc. 2002.
PERIODICALS
Lepola, Ulla. "A Controlled, Prospective, One-Year Trial of Citalopram in the Treatment of Panic Disorder." Journalof Clinical Psychiatry 59 (1998): 528-534.
