Paroxetine Imipramine

Lorazepam is a short-acting benzodiazepine indicated for use in relieving anxiety and insomnia. Lorazepam may also be administered perioperatively to alleviate pain and in status epilepticus. Imipramine is a tricyclic antidepressant, paroxetine is a selective serotonin re-uptake inhibitor, venlafaxine is a serotonin and adrenaline re-uptake inhibitor and moclobemide is a reversible monoamine oxidase inhibitor. Imipramine, paroxetine, venlafaxine and moclobemide are all classified as antidepressants. 

Some questions have been raised about the relative efficacy of the SSRls, particularly in severe depression. The pooled analyses of the data from blinded, controlled trials have tended to find similar levels of efficacy between the SSRls and the comparator TCA, imipramine. Paroxetine and fluvoxamine were both found in subanalyses of patients with severe depression included in large placebo- and imipramine-controlled studies to be more effective than imipramine in severe depression (S. A. Montgomery 1992a Ottevanger 1991 Tignol et al. 1992 Wakelin 1988]. However, imipramine may not be the TCA that is most effective in severe depression or may not have been used in the trials at an adequate dose. 

Amitriptyline -Clomipramine Desipramine Imipramine Paroxetine Antipsychotics Haloperidol Risperidone Thioridazine Codeine... 

The selectivity ratios (Fig. 21.6) show that the SNRIs, as a group, are potent selective inhibitors of the NET and that the secondary amine TCAs are substantially more potent with regard to their inhibition of NE reuptake in comparison to the SSRIs. Their in vitro affinity for inhibiting the NET essentially mirrors more or less their clinical efficacy as SNRIs (11) desipramine > protriptyline > amitriptyline = nortriptyline > reboxetine > maprotiline > amoxapine > imipramine > paroxetine. The level of affinity of the SNRIs for NET is not predictive for antidepressant activity. 

A woman taking imipramine, paroxetine and lithium, who had a 3-week continuous headaehe, was treated with 300 micrograms of dihydroergot-amine intravenously. Within 5 minutes of a subsequent 500-mierogram dose she developed dysarthria, dilated pupils, diaphoresis, diffuse weakness, and barely responded to eommands. She was diffusely hyperreflexie and showed oeeasional myoelonie jerks. She reeovered after 90 minutes. ... 

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]. 

Antidepressants Desipramine, imipramine, sertraline, fluoxetine, paroxetine, venlafaxine, bupropion, nefazodone, mirtazapine, gepirone, amineptine Mixed findings suggest that better designed studies may find a niche for some of these drugs. Amineptine was effective for withdrawal symptoms. 

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. 

Lapierre Y, Bentkover J, Schainbaum S, Manners S (1995). Direct cost of depression analysis of treatment costs of paroxetine versus imipramine in Canada. Can J Psychiatry 40, 370-7. 

Melton ST, Kirkwood CK, Farrar TW, et al (1997). Economic evaluation of paroxetine and imipramine in depressed outpatient. PsychopharmacolBull t >y 93-100. 

Gervasoni, D., Panconi, E., Henninot, V. et al. (2002). Effect of chronic treatment with milnacipran on sleep architecture in rats compared with paroxetine and imipramine. Pharmacol. Biochem. Behav. 73, 557-63. 

It has been known for over 25 years that many of the tricyclic antidepressants (TCAs), e.g. imipramine and amitriptyline, are potent inhibitors of both norepinephrine and 5-HT reuptake. Some tricyclic antidepressants, e.g. desipramine, inhibit the uptake of norepinephrine much more potently than the uptake of 5-HT. Thus, it was unclear for some time whether the inhibition of 5-HT uptake played any role in the antidepressant action of those TCAs that possessed this pharmacological property. Recently, however, effective antidepressants such as fluoxetine, paroxetine and sertraline have been marketed and these SSRIs are much more potent inhibitors of the uptake of 5-HT than that of norepinephrine (Fig. 13-8). Thus, selective inhibition of the uptake of either norepinephrine or 5-HT can result in an antidepressant effect (Ch. 55). 

Generalized anxiety Duloxetine Escitalopram Paroxetine Venlafaxine XR Benzodiazepines Buspirone Imipramine Sertraline Hydroxyzine Pregabalin... 

Venlafaxine extended release, duloxetine, paroxetine, and escitalopram are FDA approved for treatment of GAD. Sertraline is also effective. Acute response and remission rates are approximately 65% and 30%, respectively. Imipramine may be used when patients fail to respond to selective serotonin reuptake inhibitors (SSRIs). In one trial, diazepam, trazodone, and imipramine had greater anxiolytic activity than placebo. 

A recent study further supported the involvement of dopamine in the mechanism of antidepressants [82]. In this study, the antidepressant-like effect of citalo-pram, paroxetine, desipramine and imipramine in the mouse forced swim test (FST) was compared with and without dopamine depletion. It was found that lesioning with 6-OHDA did not affect the response of mice to desipramine and imipramine, whereas dopamine depletion abolished the antidepressant-like effect of citalopram and paroxetine. These results suggest that the antidepressant-like effect of SSRIs in the FST requires the activation of dopaminergic pathways. 

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. 

A breakthrough in the treatment of major depression was the discovery of fluoxetine, marketed as Prozac. Fluoxetine has a mechanism of action similar to that of imipramine with an important exception. It is a selective serotonin reuptake inhibitor, an SSRI. This strongly suggests that, in some sense, the symptoms of major depression result from a deficit in serotonin specifically. By inhibiting its reuptake from the synapse, the activity of serotonin is enhanced. Two other important drugs for major depression, sertraline (Zoloft) and paroxetine (Paxil), among several others,... 

Amitriptyline, clomipramine, imipramine, desipramine, nortriptyline, trimipramine, AT-desmethylclomipramine, fluvoxamine, norfluoxetine, paroxetine, venlafaxine, sertraline Neuroleptics... 

Feighner JP, Cohn JB, Fabre LF Jr, Fieve RR, Mendels J, Shrivastava RK, Dunbar GC (1993) A study comparing paroxetine placebo and imipramine in depressed patients. J Affect Disord 28 71-79... 

In the case of social anxiety disorder, research suggests that some of the antidepressants that are effective in other anxiety disorders do not work to ease the symptoms of social anxiety disorder. This is true of the tricyclic antidepressant imipramine and fluoxetine (Prozac). The first line of treatment for the generalized form of social anxiety disorder is an SSRI such as paroxetine or sertraline. 

Venlafaxine, paroxetine, sertraline, imipramine, and trazodone have all proven effective in relieving symptoms of GAD. Venlafaxine, a combined serotonin and norepinephrine reuptake blocker, may be an exceptionally good choice for people who have other psychiatric illnesses in addition to GAD, or when it is not clear whether the patient has GAD or a depressive illness, or both. Although, to date, only certain SSRIs have been... 

Several preliminary lines of research have started to suggest that antidepressants, once considered ineffective in generalized anxiety disorder, may be very efficacious [Gorman and Kent 1999]. In particular, venlafaxine has been effective in treating generalized anxiety disorder in both open-label and double-blind trials, and imipramine and paroxetine were as effective as a benzodiazepine in the long-term treatment of generalized anxiety disorder. 

A meta-analysis (Boyer 1995) has compared some serotonin reuptake inhibitors (paroxetine, fluvoxamine, zimeldine, and clomipramine) with imipramine and alprazolam in the alleviation of panic attacks in patients with DSM-III or DSM-III-R panic disorder. Although all three classes of drugs were shown to be significantly more effective than placebo, the serotonin reuptake inhibitors were also significantly superior to both imipramine and alprazolam. The findings of this meta-analysis highlight the importance of... 

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 ... 

Jakovljevic M, Mewett S Comparison between paroxetine, imipramine and placebo in preventing recurrent major depressive episodes. Eur Neuropsychopharmacol 1 440, 1991... 

Katona CL, Hunter BN, Bray J A double-blind comparison of the efficacy and safety of paroxetine and imipramine in the treatment of depression with dementia. Int J Geriatr Psychiatry 13 100-108, 1998... 

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