Article: Escitalopram

Escitalopram
Systematic (IUPAC) name
S-(+)-1-[3-(dimethylamino)propyl]- 1-(p-fluorophenyl)- 5-phthalancarbonitrileoxalate
Identifiers
CAS number	128196-01-0
ATC code	N06AB10
PubChem	146570
DrugBank	APRD00683
Chemical data
Formula	C20H21N2FO
Mol. weight	324.392 g/mol (414.40 as oxalate)
Pharmacokinetic data
Bioavailability	80%
Protein binding	~56%
Metabolism	Liver, specifically the enzymes CYP3A4 and CYP2C19
Half life	27-32 hours
Excretion	?
Therapeutic considerations
Pregnancy cat.	C
Legal status
Routes	Oral

Escitalopram is a medication developed by the Danish pharmaceutical company Lundbeck, that acts as a selective serotonin reuptake inhibitor or SSRI. It is typically used as an antidepressant to treat depression associated with mood disorders although also may be used in the treatment of body dysmorphic disorder and anxiety, including OCD. In the United States, the drug is marketed under the name Lexapro® by Forest Laboratories, Inc. In Canada and Europe, the drug is marketed under the name Cipralex® by Lundbeck Canada, Inc.

Manufacture and History

Escitalopram oxalate is derived from the drug citalopram which is made up of two mirror-image isomers, only one of which is thought to be an effective medication. Lundbeck has split the isomers apart, taken the active isomer and has licensed it as the new drug escitalopram. Escitalopram is the pure S-enantiomer (left-handed isomer) of the racemic bicyclic phthalane derivative citalopram, and is the most selective SSRI.

Escitalopram was released shortly before the patent for citalopram was due to expire. The expiration of a patent means other companies can legally produce cheaper generic versions. On May 23, 2006, the FDA approved the generic version of escitalopram [1] . Escitalopram is subject to a new patent. Critics have argued that escitalopram, and the subsequent marketing campaign to persuade mental health professionals to prescribe it, is a cynical ploy to promote sales of a virtually identical but considerably more expensive drug. In defense of the new drug, Lundbeck has claimed that the drug has additional benefits over the older citalopram and other antidepressant drugs on the market, mainly better tolerability [2].

Withdrawal symptoms

A possible withdrawal symptom from Escitalopram is a type of spontaneous nerve pulse, described by some patients as a feeling of small electric shocks, which may be accompanied by dizziness. These pulses may be short in duration, only milliseconds long, affect any region of the body, and recur up to several times a minute, throughout all waking hours. They can be increased by physical activity, but are not solely linked to muscular activity. Other withdrawal symptoms include extreme sensitivity to loud sounds and bright lights, chills, hot flashes, cold sweats, reddening of the face, abdominal pain, and extreme mental fatigue. [3]

Some people discontinuing use of Escitalopram report extremely vivid nightmares while others report that they feel as though they're intoxicated while awake. Emotionally, those experiencing withdrawal often feel like they are on the verge of tears for no particular reason, have little self-worth, and thoughts of self-harm.

Other studies suggest that the incidence rate of withdrawal symptoms are mild and comparable to that of placebo, citing escitalopram as "very well tolerated". [4]