I think I have found some good research articles and case studies for
you regarding the effect of citalopram (Celexa) on weight regulation.
As I mentioned above, I am only able to give you citations and (where
available) abstracts for these articles due to copyright restrictions.
There is a wide body of literature discussing the risk of SIADH
(inappropriate secretion of anti-diuretic hormone) in patients,
particularly the elderly, who are taking citalopram. Since you do not
seem particularly interested in this condition I am not including the
citations to those articles. If you would like to see them please let
me know and I'll add them in a clarification of my answer. SIADH is
linked, in most cases, to hyponatremia - basically the opposite of
dehydration (that's too simplistic an explanation, I know, sorry!).
Here are three articles that link citalopram (and other SSRIs) to body
weight change (in this case, it turns out to be weight gain) in
various study populations. Note that two are comparisons of
citalopram either to a combination therapy or to other, similar SSRIs.
1: Am J Psychiatry. 2005 Jan;162(1):192-3.
Quetiapine-induced weight gain and escitalopram.
Holzer L, Paiva G, Halfon O.
PMID: 15625223 [PubMed - indexed for MEDLINE]
2: J Clin Psychiatry. 2004 Oct;65(10):1394-9.
Response acceleration with mirtazapine augmentation of citalopram in
obsessive-compulsive disorder patients without comorbid depression: a pilot
Pallanti S, Quercioli L, Bruscoli M.
BACKGROUND: Therapeutic action of selective serotonin reuptake inhibitors
(SSRIs) is delayed from 8 to 12 weeks in patients with obsessive-compulsive
disorder (OCD). Several different agents have been tested to reduce the SSRI
therapeutic latency time. Mirtazapine, an antagonist at alpha2-adrenoceptors,
does not enhance serotonin (5-HT) neurotransmission directly but disinhibits the
norepinephrine activation of 5-HT neurons and thereby increases 5-HT
neurotransmission by a mechanism that may not require a time-dependent
desensitization of receptors. The present study was undertaken to determine
whether the mirtazapine-citalopram combination could induce an earlier and/or
greater effect on the 5-HT system in OCD subjects than citalopram alone. METHOD:
Forty-nine patients with OCD (DSM-IV) without comorbid depression were randomly
assigned to a 2-tailed, single-blind, 12-week clinical trial with citalopram
(20-80 mg/day) plus placebo or citalopram plus mirtazapine (15-30 mg/day).
Assessments were performed weekly with the Yale-Brown Obsessive Compulsive Scale
(YBOCS), the Hamilton Rating Scale for Depression, and the Clinical Global
Impressions scale. Data were collected from November 2001 to July 2003. RESULTS:
The citalopram plus mirtazapine group achieved a reduction of at least 35% in
YBOCS score and a "much improved" or "very much improved" rating on the Clinical
Global Impressions-Improvement scale from the fourth week, while the citalopram
plus placebo group obtained these results only from the eighth week. The number
of responders was higher in the citalopram plus mirtazapine group at the fourth
week of treatment, while no difference between groups in the response rate was
noted at the eighth and twelfth weeks of treatment. CONCLUSIONS: We found an
earlier onset of response action in OCD symptoms and reduced undesired side
effects when mirtazapine was added to citalopram. This augmentation strategy
deserves clinical and research consideration through further double-blind,
Randomized Controlled Trial
PMID: 15491244 [PubMed - indexed for MEDLINE]
3: J Clin Psychiatry. 2004 Oct;65(10):1365-71.
Weight gain during long-term treatment of obsessive-compulsive disorder: a
prospective comparison between serotonin reuptake inhibitors.
Maina G, Albert U, Salvi V, Bogetto F.
BACKGROUND: The effect of extended anti-depressant treatment on weight has been
poorly investigated. Also unknown is whether different compounds have
differential effects. The aim of the present study was to assess changes in
weight in obsessive-compulsive disorder (OCD) patients treated for 2.5 years
with clomipramine or selective serotonin reuptake inhibitors. METHOD: 138 DSM-IV
OCD patients who responded to 6-month acute treatment at the Mood and Anxiety
Disorders Unit, Department of Neuroscience, University of Turin, Italy, were
followed-up for 2 years while receiving open-label clomipramine, citalopram,
fluoxetine, fluvoxamine, paroxetine, or sertraline. Patients were consecutively
recruited and followed from May 1998 to March 2003. The mean percentage change
in weight was compared for each group, as was the proportion of patients who had
a > or = 7% weight increase from baseline. RESULTS: At the end of the 2.5-year
study period, patients had gained a mean of 2.5% of their body weight with
respect to baseline (1.58 kg); 14.5% of the total sample experienced a
significant (> or = 7%) weight increase. Within each but the fluoxetine
treatment group, paired t tests showed a significant increase in weight from
baseline to final visit. Analysis of variance showed a significant difference
between treatment groups (p = .009), with clomipramine being associated with the
highest weight increase and fluoxetine and sertraline with the lowest. A higher
proportion of clomipramine-treated patients (34.8%) gained > or = 7% in weight
as compared with sertraline and fluoxetine, which accounted for the lowest
percentage of patients with a significant weight gain (4.5% and 8.7%,
respectively), although this difference was not statistically significant.
CONCLUSION: Risk of weight gain during extended serotonin reuptake inhibitor
treatment for OCD differs depending on which compound is used. The differences
among antiobsessive drugs may affect compliance with medication and health
PMID: 15491240 [PubMed - indexed for MEDLINE]
These articles were found using the following search in the PubMed
MEDLINE database (http://www.pubmed.gov): "Body Weight changes"[MeSH]
AND "citalopram/adverse effects"[MeSH Terms] AND English[Lang]
Following up on an article referenced by #1, above, I found this
article in PubMed using a search as follows: "body weight/drug
effects"[MeSH Terms] AND "citalopram/adverse effects"[Mesh Terms].
Int Clin Psychopharmacol. 1996 Dec;11(4):273-8.
Phasic craving for carbohydrate observed with citalopram.
Bouwer CD, Harvey BH.
The serotonin selective reuptake inhibitors (SSRIs) have clinically and
ancedotally been associated with nausea and weight loss as a side effect of
their action. The tricyclic antidepressants have been linked to carbohydrate
(CHO) craving and weight gain in patients with major depressive disorders. This
side effect has been attributed to the strong anti-histaminergic actions of
these agents and is recognized as a causal factor of non-compliance in a
substantial percentage of patients. CHO craving is an important feature and
complication of the treatment of depression and is often ignored. A total of 18
patients were treated with the SSRI citalopram in our mood disorder clinic. In
eight cases there was a significant increase in CHO craving together with weight
gain shortly after initiation of treatment. The craving for CHO took on a phasic
presentation. These cases are presented, together with data on the change in
mood and anxiety symptom rating scales. Our observations appear paradoxical,
given that serotonin (5-HT) typically mediates a reduction in CHO intake and
that citalopram displays potent and select 5-HT-enchancing actions. However, the
receptor binding profile of citalopram may predict a risk for inducing this
adverse event. These, together with serotonergic, dopaminergic, histaminergic
and other possible mechanisms are discussed. A profound influence on patient
acceptability was observed, suggesting that the impact on compliance needs to be
PMID: 9031994 [PubMed - indexed for MEDLINE]
This search actually found four articles - but the other three focus
on the pharmacokinetics and other effects in rat models. Basically
citalopram lowers the desire to drink alcohol (for rats), changes how
rats behave in an open environment, and one of the racemes (mirror
structures) is more effective than the other. If you'd like to see
these please let me know and I'd be happy to share them - I'm not
entirely sure why they showed up.
However, for a number of other studies, citalopram showed either no or
negligible changes in weight. I found these by doing a search similar
to the above one, but slightly broader: "Body Weight"[MeSH] AND
"citalopram/adverse effects"[MeSH Terms] AND English[Lang]. Here's a
link to the results in PubMed:
Note that the above three articles show up in this list of nine, as
they are a narrower subset than this one. Also note that many of
these articles deal with the preclinical trials in rat models.
Here is the standard monograph (drug description) on citalopram:
http://www.mentalhealth.com/drug/p30-c04.html. As you can see from
the standard monograph, SSRIs in general (and citalopram in
particular) have known drug interactions with lots of things - not
only with marketed drugs but also with a number of herbals.
I inferred for these searches that you are particularly interested in
the aspects of metabolism that have to do with weight gain/weight
loss, which is why I chose to focus on the "body weight" subject area
within PubMed. As I noted before, the endocrine disorders and
metabolism subject areas tend to get a lot of information on SIADH
rather than on weight. If I am off base here please let me know and
I'll try to get into fair territory (sorry, baseball fan).
I did go looking for information in a number of other databases than
PubMed MEDLINE, including two alternative/complementary medicine
databases and PsycInfo. As I appear to be saving the best for last,
here is the only new article that I found (in PsycInfo, as it
Ginsberg, David L
Topiramate treatment of SSRI-induced weight gain.
Primary Psychiatry. Jan 2003; Vol 10 (1): 15-16
Selective serotonin reuptake inhibitors (SSRIs) are the most widely
prescribed antidepressants in the United States. While initially
considered to be weight neutral or even resulting in weight loss,
long-term use of SSRIs has been associated with weight gain. A trial
of treatment with the anticovulsant topiramate for SSRI-induced weight
gain in patients with anxiety disorders. Fifteen subjects, 11 women
and 4 men (Mean age=41.5 years), with a primary anxiety disorder
entered into this open-label study of topiramate treatment added to
their ongoing SSRI regimen. Six subjects had panic disorder with or
without agoraphobia, four subjects had obsessive-compulsive disorder,
three subjects had social phobia, one had generalized anxiety disorder
and one had posttraumatic stress disorder (PTSD). SSRIs administered
included paroxetine, citalopram, fluvoxamine, fluoxetine, and
sertraline. Topiramate was started at 25 mg BID, then increased by 25
mg/week to a target dose of 100 mg/day. All 15 subjects were able to
tolerate the dose titration schedule to the target dose and all
completed the trial. The study suggests that topiramate may have a
role in managing the weight gain associated with SSRIs. While in
absolute terms the magnitude of effect was modest, more robust results
might conceivably be achieved by a longer duration of topiramate
treatment or by introducing topiramate at an earlier phase of SSRI
My search for this article was "citalopram AND body weight".
So, it looks as though a small study indicates that topiramate may
help to counteract the weight gain experienced by some people taking
SSRIs, including citalopram.
Please let me know how I can help you further with this question
(preferably before rating it!). I'm happy to continue digging as
needed, or to go off on a different tangent.