Citalopram

Overview of Citalopram

Citalopram is an antidepressant medication belonging to a class of drugs called selective serotonin reuptake inhibitors (SSRIs). It is primarily used to treat major depressive disorder but may also be prescribed for other mental health conditions such as anxiety. It works by increasing the levels of serotonin, a neurotransmitter associated with mood regulation, in the brain.

Indications and Usage

Citalopram is approved for the treatment of major depressive disorder in adults. Its efficacy for long-term use, that is, for more than 6 weeks, has not been systematically evaluated in controlled trials. Therefore, the physician who elects to use Citalopram for extended periods should periodically re-evaluate the long-term usefulness of the drug for the individual patient.

Dosage and Administration

The initial dose of Citalopram is typically 20 mg once daily, with an option to increase the dose to a maximum of 40 mg per day depending on patient response and tolerance. Dose adjustments should generally occur at intervals of no less than one week. Citalopram can be taken with or without food. It should be taken at the same time each day to maintain an even level in the blood. If a dose is missed, it should be taken as soon as possible unless it is almost time for the next dose. In that case, the missed dose should be skipped to avoid taking two doses close together in time.

Special Populations

For older adults or those with liver problems, a lower starting dose may be recommended to decrease the risk of side effects. Citalopram has not been systematically studied in pregnant women or individuals under 18. It should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Because Citalopram is excreted in human milk, caution should be exercised when Citalopram is administered to a nursing woman.

Drug Interactions

Citalopram should not be used in combination with monoamine oxidase inhibitors (MAOIs) or within 14 days of stopping an MAOI. Additionally, care should be taken when using Citalopram in conjunction with other medications that affect the central nervous system, including other SSRIs, serotonin-norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants, triptans, tramadol, or St. John’s Wort.

Pharmacological Mechanism

Citalopram exerts its antidepressant effect by selectively inhibiting the reuptake of serotonin at the presynaptic neuron, which leads to an increased concentration of serotonin in the synaptic cleft and subsequent enhanced neurotransmission in the central nervous system.

Adverse Reactions and Side Effects

Common side effects of Citalopram include, but are not limited to, nausea, dry mouth, loss of appetite, tiredness, drowsiness, sweating, blurred vision, and yawning. Some patients may experience sexual side effects, such as decreased libido and difficulties with orgasm or ejaculation. Rarely, Citalopram can cause an increase in suicidal thoughts or behavior in adolescents and young adults. Immediate medical attention should be sought if patients experience serotonin syndrome symptoms, such as agitation, hallucinations, fever, sweating, shivering, rapid heart rate, muscle stiffness, twitching, loss of coordination, nausea, vomiting, or diarrhea.

Monitoring and Laboratory Tests

Patients on Citalopram should have their response to the medication regularly monitored by their healthcare provider, including assessment for improvement of depressive symptoms and for the emergence of suicidal thoughts. Before starting treatment, a baseline ECG should be considered for patients with risk factors for significant cardiac disease. Periodic monitoring of serum sodium levels should be conducted in the elderly and in other patients at risk of hyponatremia.

Overdosage Considerations

In cases of acute overdosage with Citalopram, symptoms may include nausea, vomiting, dizziness, sweating, tremors, drowsiness, and rarely, amnesia, confusion, or seizures. ECG and vital signs should be monitored alongside symptomatic and supportive treatment. There is no specific antidote for Citalopram overdosage and management is by supportive care and monitoring.

Storage and Handling

Citalopram tablets should be stored at 20°C to 25°C (68°F to 77°F), with excursions permitted between 15°C and 30°C (59°F and 86°F). The medication should be kept in a secure place out of the reach of children and should not be shared with anyone else, especially someone with a history of drug abuse or addiction.

Patient Counseling Information

Patients should be advised on the importance of taking Citalopram as prescribed, and not to alter the dose or discontinue treatment without first consulting their health care provider. Potential side effects, as well as potential signs of serotonin syndrome or suicidal thoughts, should be communicated. Women of childbearing potential should talk to their health care provider about the use of Citalopram during pregnancy or when breastfeeding. Patients should also be counseled about the potential for significant drug-drug interactions and advised to inform their healthcare provider of all the medications they are taking, including over-the-counter drugs, herbal supplements, and alcohol consumption.