Fluoxetine Clomipramine

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]. 

Decision analytic models have been constmcted to compare the costs of TCAs with those of SSRIs and other compounds. These comparisons have included imipramine or amitriptyline versus paroxetine or sertraline (Stewart, 1994) imipramine versus paroxetine Qonsson and Bebbington, 1994 McFarland, 1994 Lapierre et al, 1995) fluoxetine versus amitriptyline, clomipramine, doxepin and imipramine (Le Pen et al, 1994) venlafaxine versus amitriptyline, desipramine. 

The most effective treatment for cataplexy is the tricyclic antidepressants, fluoxetine, or venlafaxine. Imipramine, protriptyline, clomipramine, fluoxetine, and nortriptyline are effective in about 80% of patients. 

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. 

Solid phase extraction (SPE) has been used to efficiently extract several types of antidepressants, which can then be conveniently analyzed on GC-NPD. One assay extracted and analyzed viloxazine, venlafaxine, imipramine, desipramine, sertraline, and amoxapine from whole blood in one procedure (Martinez et al., 2002). The same laboratory analyzed fluoxetine, amitriptyline, nortriptyline, trimipramine, maprotiUne, clomipramine, and trazodone in whole blood in one assay (Martinez et al., 2003). SPE has also been used for the simultaneous analysis of TCAs and their metabolites by de la Torre et al. (1998). 

Martinez MA, Sanchez de la Torre C, Almarza E. 2003. A comparative solid-phase extraction study for the simultaneous determination of fluoxetine, amitriptyline, nortriptyline, trimipramine, maprotiline, clomipramine, and trazodone in whole blood by capillary gas-liquid chromatography with nitrogen-phosphorus detection. J Anal Toxicol 27 353. 

SRI Citalopram Clomipramine Fluoxetine Fluvoxamine Paroxetine Sertraline... 

Monoamine Oxidase Inhibitors (MAOIs). Controlled trials comparing the M AOl phenelzine to clomipramine or fluoxetine have produced mixed results. Given the limited data regarding any efficacy of MAOIs in the treatment of OCD coupled with their potentially dangerous interactions, we cannot recommend MAOIs in the treatment of OCD until other approaches have been tried. 

Serotonin-Boosting Antidepressants. Antidepressants that enhance serotonin activity in the brain have also been studied in ADHD. In particular, fluoxetine (Prozac) and the serotonin-selective TCA clomipramine (Anafranil) have been the most extensively evaluated, with mixed success. They provide some benefit for aggression and impulsivity but don t significantly improve the poor attention of ADHD. As a result, the SSRls and other serotonin-boosting antidepressants do not appear to be effective first-line treatments for ADHD. Conversely, depressed patients without ADHD often show improvements in symptoms of concentration and attention when treated with a SSRI. Although SSRls are not widely used in the treatment of ADHD, they may be worthy of consideration in ADHD patients whose impulsivity is not controlled by stimulants alone. Those with comorbid conduct disorder or ODD who are prone to agitation and at times violent outbursts may be helped by the addition of a SSRI. 

Zohar and Insel have suggested that the s)nnptoms of obsessive-compulsive disorder are due to supersensitive 5-HTi-type receptors and that the function of SSRIs such as clomipramine, fluoxetine and the non-selective 5-HT antagonist metergoline owe their efficacy to their ability to reduce the activity of these receptors. 

Changing a patient from one MAOI to another, or to a TCA, requires a "wash-out" period of at least 2 weeks to avoid the possibility of a drug interaction. There is evidence to suggest that a combination of an MAOI with clomipramine is more likely to produce serious adverse effects than occurs with other TCAs. Regarding the newer non-tricyclic antidepressants, it is recommended that a "wash-out" period of at least 5 weeks be given before a patient on fluoxetine is given an MAOI this is due to the very long half-life of the main fluoxetine metabolite norfluoxetine. 

The prototypical serotonin reuptake inhibitor (SRI) medication is the non-selective agent clomipramine, a tricyclic antidepressant (TCA). The Selective SRIs (SSRIs) include fluoxetine (Prozac), sertraline (Zoloft), paroxetine (Paxil), fluvoxamine (Luvox), and citalo-pram (Celexa). The Food and Drug Administration (FDA) approved clinical indications for these medications are described in Table 22.1. 

A potential limitation of most of the controlled studies discussed above relates to the numerous exclusion criteria used for patient selection. For example, in order to find homogenous samples, major depression, bipolar disorder, Tourette s disorder, psychosis (clomipramine, fluvoxamine and fluoxetine trials), primary psychiatric disorder other than OCD (clomipramine and sertraline trials), and attention deficit/hyperactivity disorder (ADHD), autism, or other developmental disorders (clomipramine and fluoxetine trials) were excluded. Thus it remains unknown how well these controlled studies will generalize to more naturalistic clinical populations that are highly comorbid and where exclusion criteria are not applied. 

FIGURE 39.2 Treatment algorithm for pediatric obsessive-compulsive disorder (OCD). In adjusting cognitive behavior therapy (CBT), increase frequency or intensity, or alter the setting or format, e.g., have it be home based or day treatment. CMI, clomipramine DMI, desipramine NT, nortriptyline SSRI, selective serotonin reuptake inhibitor (fluoxetine, fluvoxamine, paroxetine, sertraline, citalopram). 

Simeon, J. and Thatte, S. (1990) Treatment of adolescent obsessive-compulsive disorder with clomipramine-fluoxetine combination. Psychopharmacol Bull 26 285—290. 

In the Zito et al. study (2000), antidepressants were the second most commonly prescribed psychotropic medication. There are a total of 10 studies or case reports in the literature examining antidepressant use in preschool children (Table 49.4). None of the 10 studies are randomized, double-blind, or placebo-controlled trials. The ten uncontrolled studies looked at a total of 37 preschool children. Six of the studies looked at a total of 29 preschoolers with autism or childhood schizophrenia (Campbell et ah, 1971a Petti and Campbell, 1975 Holttum et ah, 1994 Sanchez et ah, 1996 DeLong et ah, 1998 Hollander et ah, 2000). While these six studies are difficult to compare, given the small sample sizes and the different treatment medications, these open-label studies suggest that clomipramine, venlafaxine, and fluoxetine may be helpful to reduce some psychiatric symptoms found in autistic... 

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. 

In most cases, SSRIs are the first choice for drugs to combat OCD. Clomipramine, fluvoxamine, fluoxetine, paroxetine, sertraline, and citalopram are all SSRIs that have been proven effective in reducing OCD symptoms. However, in about 40 to 60% of patients, these drugs do not completely alleviate all the symptoms. When this is the case, a second type of drug called a neuroleptic is often added. Neuroleptic drugs, such as haloperidol, clozapine, risperidone, and chlorpromazine... 

Note. BROF = brofaromine CIT = citalopram CLO = clomipramine CT = cognitive therapy Dx = diagnosis EXP = exposure in vivo FLU = fluvoxamine FLUOX = fluoxetine GAD = generalized anxiety disorder 5-HTP = 5-hydrox3rtryptophan IMl = imipramine MAP = maprotiline OCD = obsessive-compulsive disorder PAR = paroxetine PD = panic disorder PLA = placebo PPM = psychological panic management RIT = ritanserin ... 

Citalopram and fluoxetine also have been studied in panic disorder (Michelson et al. 1998 Wade et al. 1997). Citalopram was compared with clomipramine. At the most effective citalopram dose (20-30 mg/day), approximately 58% of patients were panic-free compared with 50% of patients receiving clomipramine and 32% of placebo patients. All rating scales suggested that 20 or 30 mg/day of citalopram was more effective than 40 or 60 mg/day of citalopram. Finally, data support the efficacy of fluoxetine in panic disorder. In a study comparing 10 and 20 mg/day of fluoxetine and placebo, fluoxetine treatment, particularly the 20-mg daily dose, was associated with more improvement than placebo across multiple measures, including functional impairment. 

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