Description
Clomipramine is a tricyclic antidepressant, the 3-
chlorinated derivative of imipramine . Like imipramine, clomipramine potently inhibits serotonin and norepinephrine reuptake (K
is = 7.4 and 96 nM, respectively). It also is an antagonist at histamine, muscarinic acetylcholine, α
1-
adrenergic, and dopamine receptors (K
ds = 31, 37, 38, and 190 nM for H
1, M
1, α
1, and D
2, respectively).
Chemical Properties
Off-White Solid
Originator
Anafranil,Ciba Geigy,Switz.,1968
Uses
Potent, selective 5-HT uptake blocker
Uses
anti-depressant, serotonin uptake inhibitor
Uses
Serotonin reuptake inhibitor. Antidepressant; antiobsessional agent
Definition
ChEBI: A hydrochloride resulting from the reaction of equimolar amounts of clomipramine and hydrogen chloride. One of the more sedating tricyclic antidepressants, it is used for the treatment of depression as well as obsessive-compulsive disorder and phobias.
Manufacturing Process
22.9 parts of 3-chloroiminodibenzyl are dissolved in 300 parts by volume of
xylene, and 4 parts of sodium amide, pulverized and suspended in toluene,are added thereto while stirring and maintaining the whole under a nitrogen
atmosphere. The xylene solution immediately turns dark colored, but upon
crystallization of the sodium salt therefrom it becomes again light-colored. The
reaction mixture is stirred for about 2 hours at 80°C until the development of
ammonia has terminated. A solution of γ-dimethylaminopropyl chloride in
toluene, prepared by setting free a corresponding amount of the free base
from 17.4 parts of its hydrochloride salt by addition of aqueous sodium
hydroxide solution in about 10% excess, extraction with toluene and drying
for 2 hours over anhydrous sodium sulfate is added to the xylene solution
containing the sodium salt mentioned above and the whole is stirred under
reflux for 15 hours. Precipitated sodium chloride is filtered off and the filtrate
is concentrated. The residue is diluted with ether, and the hydrochloride of 3-
chloro-5-(γ-dimethylaminopropyl)-iminodibenzyl is precipitated by introducing
dry, gaseous hydrogen chloride. It is filtered off under suction and purified by
repeated recrystallization from acetone; the pure substance melts at 191.5°C
to 192°C.
brand name
Anafranil (Tyco).
Therapeutic Function
Antidepressant
General Description
Clomipramine (Anafranil) is up to 50 times as potentas imipramine in some bioassays. This does not implyclinical superiority, but it might be informative about tricyclicand, possibly, other reuptake inhibitors. The chloro replacingthe H-substituent could increase potency by increasingdistribution to the CNS, but it is unlikely that this wouldgive the potency magnitude seen. It might be conjecturedthat an H-bond between the protonated amino group (as invivo) and the unshared electrons of the chloro substituent might stabilize a β-arylamine–like shape and give moreefficient competition for the transporter. The drug is anantidepressant. It is used in obsessive–compulsive disorder,an anxiety disorder that may have an element of depression.
Biological Activity
Potent, selective 5-HT uptake blocker. Antidepressant. Binds to the human 5-HT transporter with a K i of 0.05 nmol/l. Also available as part of the Serotonin Uptake Inhibitor Tocriset™ .
Veterinary Drugs and Treatments
In veterinary medicine, clomipramine is used primarily in dogs as
a treatment for obsessive-compulsive disorders (ritualistic stereotypical
behaviors) and may be useful for dominance
aggression and
anxiety (separation).
Clomipramine may also be useful in cats, particularly for behaviors
such as urine spraying. One prospective, double-blinded
controlled study in cats with psychogenic alopecia comparing clomipramine
(0.5 mg/kg PO daily) versus placebo showed no statistic
differences in study parameters (Mertens, Torres et al. 2006).
Drug interactions
Potentially hazardous interactions with other drugs
Alcohol: increased sedative effect.
Analgesics: increased risk of CNS toxicity with
tramadol; possibly increased risk of side effects with
nefopam; possibly increased sedative effects with
opioids.
Anti-arrhythmics: increased risk of ventricular
arrhythmias with amiodarone - avoid; increased
risk of ventricular arrhythmias with disopyramide,
flecainide or propafenone; avoid with dronedarone.
Antibacterials: increased risk of ventricular
arrhythmias with delamanid and moxifloxacin and
possibly telithromycin - avoid with delamanid and
moxifloxacin.
Anticoagulants: may alter anticoagulant effect of
coumarins.
Antidepressants: possibly increased serotonergic
effects with duloxetine; enhanced CNS excitation
and hypertension with MAOIs and moclobemide;
concentration possibly increased with SSRIs; risk
of ventricular arrhythmias with citalopram and
escitalopram - avoid; possible increased risk of
convulsions with vortioxetine.
Antiepileptics: convulsive threshold lowered;
concentration reduced by carbamazepine,
phenobarbital and possibly fosphenytoin, phenytoin
and primidone.
Antimalarials: avoid with artemether/lumefantrine
and piperaquine with artenimol.
Antipsychotics: increased risk of ventricular
arrhythmias especially with droperidol, fluphenazine,
haloperidol, pimozide, sulpiride and zuclopenthixol
- avoid; increased risk of ventricular arrhythmias
with risperidone; increased antimuscarinic effects
with clozapine and phenothiazines; concentration
increased by antipsychotics.
Antivirals: increased risk of ventricular arrhythmias
with saquinavir - avoid; concentration possibly
increased with ritonavir.
Atomoxetine: increased risk of ventricular
arrhythmias and possibly convulsions.
Beta-blockers: increased risk of ventricular
arrhythmias with sotalol.
Clonidine: tricyclics antagonise hypotensive
effect; increased risk of hypertension on clonidine
withdrawal.
Cytotoxics: increased risk of ventricular arrhythmias
with arsenic trioxide.
Dapoxetine: possibly increased risk of serotonergic
effects - avoid.
Dopaminergics: avoid use with entacapone; CNS
toxicity reported with selegiline and rasagiline.
Methylthioninium: risk of CNS toxicity - avoid if
possible.
Metabolism
Clomipramine is extensively demethylated during
first-pass metabolism in the liver to its primary active
metabolite, desmethylclomipramine. Clomipramine has
been estimated to have a plasma elimination half-life of
about 21 hours; that of desmethylclomipramine is longer
(about 36 hours).
Paths of metabolism of both clomipramine and
desmethylclomipramine include hydroxylation and
N-oxidation. About two-thirds of a single dose of
clomipramine is excreted in the urine, mainly in the form
of its metabolites, either free or in conjugated form; the
remainder of the dose appears in the faeces.
References
[1] HRDINA P D. Pharmacology of serotonin uptake inhibitors: focus on fluvoxamine.[J]. Journal of Psychiatry & Neuroscience, 1991, 16 2 Suppl 1: 10-18.
[2] MASAHIKO TATSUMI . Pharmacological profile of antidepressants and related compounds at human monoamine transporters[J]. European journal of pharmacology, 1997, 340 2: Pages 249-258. DOI:
10.1016/s0014-2999(97)01393-9
