Clomipramine side effects

Antidepressants are used in the treatment of neuropathic pain and headache. They include the classic tricyclic compounds and are divided into nonselective nor-adrenaline/5-HT reuptake inhibitors (e.g., amitriptyline, imipramine, clomipramine, venlafaxine), preferential noradrenaline reuptake inhibitors (e.g., desipramine, nortriptyline) and selective 5-HT reuptake inhibitors (e.g., citalopram, paroxetine, fluoxetine). The reuptake block leads to a stimulation of endogenous monoaminer-gic pain inhibition in the spinal cord and brain. In addition, tricyclics have NMDA receptor antagonist, endogenous opioid enhancing, Na+ channel blocking, and K+ channel opening effects which can suppress peripheral and central sensitization. Block of cardiac ion channels by tricyclics can lead to life-threatening arrhythmias. The selective 5-HT transporter inhibitors have a different side effect profile and are safer in cases of overdose [3]. 

Treatment with imipramine, the most studied TCA, leaves 45% to 70% of patients panic free. Both desipramine and clomipramine have demonstrated effectiveness in PD as well. Despite their efficacy, TCAs are considered second- or third-line pharmacotherapy due to poorer tolerability and toxicity on overdose.48,49 TCAs are associated with a greater rate of discontinuation from treatment than SSRIs.53 PD patients taking TCAs may experience anticholinergic effects, orthostatic hypotension, sweating, sleep disturbances, dizziness, fatigue, sexual dysfunction, and weight gain. Stimulant-like side effects occur in up to 40% of patients.49... 

The tricyclic antidepressant clomipramine also has been studied for PMDD. In placebo-controlled trials, both continuous daily dosing and luteal phase administration proved effective.17 Compared with the SSRIs, however, clomipramine has a less desirable side-effect profile with low tolerability. 

If treatment with an SSRI or another antidepressant such as clomipramine is not successful, hormonal treatment with a GnRH agonist, such as leuprolide, maybe considered. The use of leuprolide improves premenstrual emotional symptoms as well as some physical symptoms such as bloating and breast tenderness. Cost, the need for intramuscular administration, and the side effects of hypoestrogenism (e.g., vaginal dryness and hot flashes) limit its use. 

In addition to this serious diet-drug interaction, irreversible MAOIs also potentiate the effects of sympathomimetic drugs like ephedrine found in over-the-counter cold remedies and recreational stimulants like amphetamine. The MAOIs also interact with drugs that increase synaptic concentrations of 5-HT, such as the tricyclic antidepressant clomipramine and the herbal SSRI antidepressant St John s wort (Hypericum spp.). The resulting serotonin syndrome is characterised by hyperthermia and muscle rigidity. While devoid of these side effects the reversible MAO-A inhibitor moclobemide has yet to establish itself as a first-line alternative to the SSRIs. 

Tricyclic drugs have, as the name implies, a three-ring structure, and interfere with reuptake of norepinephrine and/or serotonin into axon terminals. Tricyclic drugs include imipramine (Tofranil), amitriptyline (Elavil), clomipramine (Anafranil), and nortriptyline (Pamelor, Aventil). Tricyclics have the occasional but unfortunate cardiovascular side effects of arrhythmia and postural hypotension. Newer, nontricyclic antidepressants have been developed that are collectively referred to as SSRIs. These have a potent and selective action on serotonin, and lack the cardiovascular side effects of the tricyclics. These include fluoxetine (Prozac), paroxetine (Paxil), sertraline (Zoloft), and fluvoxamine (Luvox). A fifth SSRI, citalopram (Celexa) has been used in Europe and has recently been approved in the United States. Venlafaxine (Effexor) blocks reuptake of norepinephrine and serotonin, while bupropion (Wellbutrin) acts on both dopamine and norepinephrine. 

The traditional scheme is complicated by the fact that some antidepressants exhibit characteristics of more than one class. For example, clomipramine, a tricyclic antidepressant (TCA) with side effects and toxicity similar to other TCAs, works more like the selective serotonin reuptake inhibitors (SSRls). Similarly, venlafaxine and duloxetine, which are usually grouped with the atypical antidepressants, have a side effect and safety profile comparable to the SSRls. Although a classihcation system based on mechanism of action offers some advantage (see Table 3.7), even this scheme is limited by the fact that antidepressants that work in the same way may have widely divergent side effect and safety profiles. In the following discussion, the traditional classification system is adopted. Although fraught with problems and inconsistencies. 

Tricyclic Antidepressants (TCAs). The TCAs, particularly imipramine (Tofranil), were also discovered soon after their introduction to be effective in the treatment of panic attacks. Imipramine, the best-studied TCA in the treatment of panic disorder, is most often helpful at daily doses of 150-250 mg, though it must be started at 10-25 mg, usually at bedtime, and gradually increased over 2-4 weeks. Although they are not as well studied, many clinicians prefer to use the secondary amine TCAs, desipramine (Norpramin) and nortriptyline (Pamelor), because they have milder side effects than imipramine. Clomipramine (Anafranil), though probably the TCA with the greatest side effect burden, is often said to be most effective in patients with refractory disease. 

The effective dose range for treating OCD is 150-300 mg/day. Side effects associated with clomipramine are similar to or slightly more severe than those observed with other TCAs and are described in more detail in Chapter 3. 

Despite its considerable efficacy, clomipramine has given way to the SSRls as a result of their more favorable side effect and safety profiles. Clomipramine, however, is often used as an augmenfafion sfrategy for OCD pafienfs who are partial responders to SSRl therapy. The effectiveness of this approach has not been verified in confrolled frials. Furthermore, coadministration of clomipramine with some of the SSRls can result in potentially dangerous drug interactions. 

In the event that the initial SSRI provides an unsatisfactory treatment response, preferred alternatives include (1) switching to another SSRI, (2) switching to ven-lafaxine or duloxetine, or (3) switching to clomipramine. Despite limited data to date regarding their efficacy, SNRls are included as alternatives prior to considering clomipramine due to their more favorable safety and side effect profiles. 

CLOMIPRAMINE /-/YDROC/-/LOR/DE Administer in divided doses with meals to reduce Gl side effects. After titration, the total daily dose may be given once/day at bedtime to minimize daytime sedation. 

This group includes compounds with actions on a range of neurotransmitter systems. Their antidepressant efficacy is mediated by reuptake inhibition of serotonin and noradrenaline, although side-effects such as sedation may also be useful. Their use in anxiety disorders is supported by a long history of clinical experience and a reasonable evidence base from controlled trials. Studies support the use of clomipramine (a potent serotonin reuptake inhibitor) in panic disorder and OCD (Lecrubier et al. 1997 Clomipramine Collaborative Study Group 1991), of imipramine in panic disorder and GAD (Cross-National Collaborative Panic Study 1992 Rickels et al. 1993), and of amitriptyline in PTSD (Davidson et al. 1993a). No controlled studies support the use of TCAs in social anxiety disorder. 

This chapter describes the structure and neurochemical function of TCAs, metabolism and significant interactions with other medications, side effects, and specific recommendations for monitoring of side effects in children and adolescents. Because of the recent concern regarding the sudden deaths of children stabilized on TCAs, particular attention will be paid to the potential cardiovascular effects of these medications. The chapter will focus on the five TCA medications that have been most widely used in children amitriptyline (AMI), nortriptyline (NT), imipramine (IMI), desipratnine (DMI), and clomipramine (CMI). 

The study of TCAs in children with OCD led directly from the use of these medications in adults with similar symptoms. Findings have shown significant advantage with both CMI and DMI over placebo in the treatment of this illness (Flament et al., 1985 deVaugh-Geiss et al., 1992). Clomipramine is the only TCA with a distinct indication from the FDA for the treatment of OCD. Use of TCAs has recently been supplanted by selective serotonin reuptake inhibitor (SSRI) medications that may have a more favorable side effect profile. 

Because of their better side effect profile compared with clomipramine, including their lower propensity to decrease the seizure threshold, selective SRIs (SSRIs) have been receiving increasing attention as a treatment for the interfering symptoms associated with autistic disorder and other PDDs. 

ADHD, attention-deficit hyperactivity disorder BP, blood pressure CLO, clomipramine FLX, fluoxetine IMP, imipramine N, total number of subjects in study ( ), number of preschool-age subjects in study P, pulse rate PDD-NOS, pervasive developmental disorder, not otherwise specified SE, side effect VNF, venlafaxine. DSM-III-R or DSM-IV criteria used not specified by authors. 

Imipramine, amitriptyline, clomipramine, trimipramine, and doxepin are tertiary amine TCAs. Desipramine, nortriptyline, and protriptyline are secondary amine TCAs. Tertiary amine tricyclics have more potent serotonin reuptake inhibition, and secondary amine tricyclics have more potent noradrenergic reuptake inhibition. Tertiary amine TCAs tend to have more side effects than do... 

Imipramine, amitriptyline, doxepin, desipramine, clomipramine, and trimipramine therapy can be initiated at 25-50 mg/day. Divided dosing may be used at first to minimize side effects, but eventually the entire dose can be given at bedtime. The dose can be increased to 150 mg/day the second week, 225 mg/day the third week, and 300 mg/ day the fourth week. The dose of clomipramine should not exceed 250 mg/day because of an increased risk of seizures at higher doses. 

Treatment of GAD can be undertaken using a number of pharmacological agents. Benzodiazepines have been found to be superior to placebo in several studies and all benzodiazepines appear to be equally effective. However, side effects include sedation, psvchomotor impairment, amnesia and tolerance (Chapter 1). Recent clinical data indicate that SSRIs and SNRIs are effective in the treatment of acute GAD symptoms. Venlafaxine, paroxetine and imipramine have been shown to be effective antianxiety medications in placebo-controlled studies. Case studies also indicate the usefulness of clomipramine, nefazodone, mirtazapine, fluoxetine and fluvoxamine in GAD. Buspirone, a 5-HTla receptor partial agonist, has been shown to be effective in several placebo-controlled, double-blind trials (Roy-Byme and Cowley, 2002). Buspirone has a later onset of action than both benzodiazepines and SSRIs but with the advantage of being non-addictive and non-sedating. 

The Food and Drug Administration (FDA) has approved clomipramine for the treatment of obsessive-compulsive disorder. Clomipramine is also used in the United States, Europe, Canada, England, and, indeed, most of the world as an antidepressant. In six random-assignment, double-blind studies, this agent was equal in efficacy to standard tricyclics, with a side-effect profile comparable with other TCAs ( Table 7-6). 

Of the tricyclic antidepressants used, clomipramine has been shown to be effective in the treatment of children with obsessional symptoms, effects which have been shown to be independent of the antidepressant action of the drug. More recent studies have provided evidence that the SSRI antidepressants such as fluoxetine are as effective, with fewer side effects. 

Capstick N. Psychiatric side-effects of clomipramine (Anafranil). J Int Med Res 1973 1 444. 

McLean JD, Forsythe RG, Kapkin IA. Unusual side effects of clomipramine associated with yawning. Can J Psychiatry 1983 28(7) 569-70. 

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