Citalopram (Celexa, Cipramil) is an antidepressant which belongs to the class of Selective Serotonin Re-uptake Inhibitors (SSRI).
Citalopram works by inhibiting the reuptake of serotonin into the pre-synaptic plate; (it also effects the reuptake of other neurotransmitters, such as nor-adrenalin, but these additional effects are very minor and are of no clinical relevance). This leads to an increase in serotonin turnover, by increasing the amount of serotonin within the synaptic gap (and thus the amount of serotonin available to bind to the post-synaptic receptor plate). It is this mechanism that is thought to mediate its antidepressant activity.
Introduction to Citalopram
The efficacy of SSRI's is actually disputed. Some trials have reported SSRI's as being little more effective than placebo, although in trials where patients suffered from severe depression it was found that SSRI medication was significantly more effective than placebo.[1]
Citalopram is frequently prescribed as a "1st line medication" in order to treat depression. It is also prescribed to treat anxiety disorders, Panic attacks and OCD.
Citalopram is typically taken in one dose at any time of the day. It comes in 10mg , 20mg , 40mg, and 60mg tablets.Dosages typically range from 10-60mg. When first prescribing to a patient, a starting dose of 10 or 20mg is offered. After a few weeks the starting dose is often increased gradually until anti-depressant effect is satisfactory. It is increased gradually in order to minimize the occurrences of side effects.
Citalopram is also frequently used off-label to treat Premenstrual Dysphoric Disorder (a severe form of Pre-menstrual Syndrome) and Body Dysmorphic Disorder.Citalopram has been found to greatly reduce the symptoms of diabetic neuropathy and Premature Ejaculation. There is also evidence that
Citalopram may be effective in the treatment of post-stroke pathological crying.
While on its own Citalopram is less effective than Amitriptyline in the prevention of migraines, in refractory cases combination therapy may be more effective.
Citalopram and other SSRI's can be used to treat hot flashes.
A 2009 multisite randomized controlled study found no benefit and some adverse effects in autistic children from Citalopram, raising doubts whether SSRI's are effective for treating repetitive behavior in children with autism.
Some research suggests that Citalopram interacts with Cannabinoid protein-couplings in the rat brain. This is put forward as a potential cause of some of the drug's antidepressant effect.
Side Effects of Citalopram
Side effects of Citalopram are usually gastro-intestinal. Nausea has often been reported upon initial treatment. To minimize the side effects it is recommended by pharmacists to take the medicine after eating a meal. Food does not effect the rate of the drugs absorption.
Other side effects reported include insomnia, weight changes, drowsiness, decreased sex drive and anorgasmia (inability to achieve orgasm).
Less common side effects include, bruxism (grinding teeth), vomiting, cardiac arrhythmia (a condition where there is abnormal electrical activity in the heart), blood pressure changes, anxiety, mood changes and headache.
Sexual dysfunction is often a side effect of SSRI's. Although usually reversible, these sexual side effects can last for months or years after the drug has been completely withdrawn. This is known as post SSRI sexual dysfunction.
Citalopram theoretically causes side effects by increasing the amount of serotonin in other parts of the body (eg the intestines). Other side effects such as increased apathy and emotional flattening may be caused by the decrease in dopamine release that is associated with increased serotonin.
Citalopram is also a very mild H1 antagonist (anti histamine ) and this may be responsible for some of its sedating effects.
SSRI withdrawal syndrome
Patients often stay on anti-depressants for a very protracted period of time. This is probably partly because of the withdrawal syndrome which ensues upon discontinuation of the drug. Patients also stay on the medication due to the improvement in their state of mind and their wish for this to be continued indefinitely.
Upon withdrawal from Citalopram (or a reduction in dose) some users report "electric shock sensations", dizziness, anxiety, sweating, insomnia and tremor. The severity of symptoms that occur when discontinuing Citalopram can be reduced by carefully lowering the dose with a sufficient time in between dose reductions.
Dangers
Overdoseage
Overdosage may result in vomiting, sedation, disturbances in heart rhythm, dizziness, sweating, nausea, tremor, and rarely amnesia, confusion, coma, or convulsions. A number of overdose deaths have occurred, sometimes involving other drugs but also with citalopram as the sole agent. Citalopram and N-desmethylcitalopram may be quantitated in blood or plasma to confirm a diagnosis of poisoning in hospitalized patients or to assist in a medicolegal death investigation. Blood or plasma Citalopram concentrations are usually in a range of 50-400 μg/L in persons receiving the drug therapeutically, 1000-3000 μg/L in patients who survive acute overdosage and 3–30 mg/L in those who do not survive.Interactions
Because of Citalopram's serotonergic effects, great caution should be taken when considering co-administration with other serotonergic drugs because of the risk of a dangerous increase in serotonin levels which could lead to Serotonin Syndrome. Other serotonergic substances include St John's Wort (which has purported SSRI mimic effects itself), tryptophan, 5-htp (5-hydroxy tryptophan - a precursor to serotonin), MAOI antidepressants and the narcotic pain killers tramadol, tapentadol and meperidine/pethidine.Suicidality
Citalopram comes with a "black box warning" that it may increase suicidal thinking and behaviour. In the U.S. it states that it may increase suicidal thinking and behaviour in those under the age of 24". [2]
Like many SSRI's (if not all) the risk of suicide or self harm actually increases during the first few weeks of treatment. These initial side effects go away when the drug starts to "work" after a period which is usually in the region of 4-6 weeks. It is not known why side effects stemming from the drugs serotonergic activity are noticed before its therapeutic effects , but this is indeed what happens and is responsible for the initial increase in suicidal tendencies.
Chemistry of Citalopram
[3]
Column 1 Column 2 Systematic (IUPAC) name: 1-[3-(dimethylamino)propyl]-1-(4-fluorophenyl)-1,3-dihydro-2-benzofuran-5-carbonitrile Synonyms: 1-[3-(dimethylamino)propyl]-1-(4-fluorophenyl)-1,3-dihydro-5-isobenzofurancarbonitrile, 1-[3-(dimethylamino)propyl]-1-(4-fluorophenyl)-5-phtalancarbonitrile, Lu 10-171, Nitalapram; Celexa, Cipramil, Elopram, Seropram (hydrobromide) Molecular Formula: C20H21FN2O Molar mass: 324.40 g/mol, 405.31 g/mol (hydrobromide) CAS Registry Number: 59729-33-8, 59729-32-7 (hydrobromide) Melting Point: 182-183 °C (hydrobromide) Boiling Point: 175-181°C @ 0.03 mmHg Flash Point: no data Solubility: freely soluble in water, ethanol, chloroform Additionnal data: none Notes: hydrobromide aspect : white to off white fine crystals, hydrobromide crystallyzed from isopropanol