Selective serotonin reuptake inhibitor effects

MDMA overdose as well as the concomitant consumption of selective serotonin reuptake inhibitors (SSRI) with other dmgs that exert serotoninergic effects (such as inhibitors of monoamine oxidase) can rapidly lead to the serotonin syndrome. Its symptoms, which are reversible upon cessation, of the drug include confusion, muscle rigidity in the lower limbs, and hyperthermia suggesting an acute reaction to serotonin overflow in the CNS. Blocking the function of SERT outside the brain causes side effects (e.g., nausea), which may be due to elevated 5HT however , impairment of transporter function is not equivalent to direct activation of 5HT recqrtors in causing adverse effects such as fibrosis and pulmonary hypertension. 

VMATs are not inhibited by drugs such as cocaine, tricyclic antidqnessants and selective serotonin reuptake inhibitors that affect plasma membrane monoamine transport. Amphetamines have relatively selective effects on monoaminergic cells due to selective uptake by plasma membrane monoamine transporters, but their effect appears to be mediated by their ability as weak bases to reduce ApH, the driving force for vesicular monoamine transport that leads to efflux of the vesicular contents into the cytoplasm. 

There is, however, a unique risk in the bipolar form that antidepressant treatment may trigger a switch into mania. This may occur either as the natural outcome of recovery from depression or as a pharmacological effect of the drug. Particular antidepressants (the selective serotonin reuptake inhibitors) seem less liable to induce the switch into mania than other antidepressants or electroconvulsive therapy. Treatment for mania consists initially of antipsychotic medication, for instance the widely used haloperidol, often combined with other less specific sedative medication such as the benzodiazepines (lorazepam intramuscularly or diazepam orally). The manic state will usually begin to subside within hours and this improvement develops further over the next 2 weeks. If the patient remains disturbed with manic symptoms, additional treatment with a mood stabilizer may help. 

A number of non-hormonal therapies have been studied for symptomatic management of vasomotor symptoms, including antidepressants [e.g., selective serotonin reuptake inhibitors (SSRIs) and venlafaxine], herbal products (e.g., soy, black cohosh, and dong quai), and a group of miscellaneous agents (e.g., gabapentin, clonidine, and megestrol). The choice of therapy depends on the patient s concomitant disease states, such as depression and hypertension, and the risk for potential adverse effects. 

Dizziness, vertigo, nausea, vomiting, constipation, and lethargy are all relatively common adverse events. These effects are more pronounced for several days after initiation and following upward dose titration. Seizures have been reported rarely the risk is dose-related and appears to increase with concomitant use of antidepressants, such as tricyclic antidepressants or selective serotonin reuptake inhibitors. Tramadol should be avoided in patients receiving monoamine oxidase (MAO) inhibitors because tramadol inhibits the uptake of norepinephrine and serotonin. 

The effects of acute administration of selective serotonin reuptake inhibitors (SSRIs) on sleep have been studied in laboratory animals, healthy... 

Monaca, C., Boutrel, B., Hen, R., Hamon, M. Adrien, J. (2003). 5-HTia/b receptor-mediated effects of the selective serotonin reuptake inhibitor citalopram, on sleep studies in 5-HTia and 5-HTib knockout mice. Neuropharmacology 28, 850-6. 

Oberndorfer, S., Saletu-Zyhlarz, G. Saletu, B. (2000). Effects of selective serotonin reuptake inhibitors on objective and subjective sleep quality. Neuropsychobiology 42, 69 81. 

In many clinical trials a positive control of a clinically established drug is often used for comparison purposes for example, a novel selective serotonin reuptake inhibitor (SSRI), may be compared with a more established tricyclic antidepressant, such as imipramine. The aim is to see whether the new SSRI is more efficacious or has fewer adverse side effects than the more established tricyclic (Chapter 12). In many such comparisons the new and older treatments are equally efficacious at relieving depression, but the newer drugs display fewer side effects this means that they are better tolerated by patients, so that they are more willing to continue taking the tablets. The high rates of compliance also mean that, in overall terms, newer drugs with fewer side effects tend to be more efficacious. 

Until the introduction of selective serotonin reuptake inhibitors (SSRIs) in the 1980s, tricyclic antidepressants were the most widely used drugs. The therapeutic effect of amitriptyline and imipramine are related to their ability to inhibit the presynaptic reuptake of both NA and 5-HT. They are referred to as non-selective reuptake inhibitors, whereas many of the other tricyclics are more selective thus, clomipramine is a selective reuptake inhibitor for 5-HT and desipramine and nortriptyline are selective... 

The answer is d. (Kai ung, p 505.) Fluoxetine is a highly selective serotonin re uptake inhibitor (55RI) acting on the 5-1 IT transporter. It forms an active metabolite that is effective for several days. Selective serotonin reuptake inhibitors are inhibitors of cytochrome P450 isoenzymes, which is the basis of potential drug-drug interactions... 

Dexamethasone has been used successfully in the management of chemotherapy-induced nausea and vomiting (CINV) and postoperative nausea and vomiting (PONV), either as a single agent or in combination with selective serotonin reuptake inhibitors (SSRIs). For CINV, dexamethasone is effective in the prevention of both cisplatin-induced acute emesis and when used alone or in combination for the prevention of delayed nausea and vomiting associated with CINV. 

Alternatives to estrogen for hot flushes are shown in Table 31-6. Progesterone alone may be an option in women with a history of breast cancer or venous thrombosis, but side effects limit their use. For women with contraindications to hormone therapy, selective serotonin reuptake inhibitors and venlafaxine are considered by some to be first-line therapy, but efficacy of venlafaxine beyond 12 weeks has not been shown. 

Selective serotonin reuptake inhibitors are considered to be less effective than TCAs for migraine prophylaxis and should not be considered first- or second-line therapy. However, they may be beneficial when depression is a significant contributor to headache. Preliminary data suggest a possible benefit with venlafaxine. 

Treatment with a selective serotonin reuptake inhibitor is usually initiated in depressed patients with AD. Paroxetine causes more anticholinergic side effects than the other selective serotonin reuptake inhibitors. Ven-lafaxine may also be used. 

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. 

Trazodone, 25 to 100 mg, is often used for insomnia induced by selective serotonin reuptake inhibitors or bupropion. Side effects include serotonin syndrome (when used with other serotonergic drugs), oversedation, a-adrenergic blockade, dizziness, and rarely priapism. 

When treating anxiety one should of course first treat any reversible medical condition. When pharmacological treatment is necessary SSRI is most often drug of choice. Selective serotonin reuptake inhibitors are both effective and safe. Benzodiazepines that have been widely used are drugs with a relative high risk of adverse effects (see Chapter 4). Risks for dependence and abuse must always be considered for benzodiazepines. 

The most commonly used therapies for anxiety and depression are selective serotonin reuptake inhibitors (SSRIs) and the more recently developed serotonin noradrenaline reuptake inhibitors (SNRIs). SSRIs, which constitute 60% of the worldwide antidepressant and antianxiety market, are frequently associated with sexual dysfunction, appetite disturbances and sleep disorders. Because SSRIs and SNRIs increase 5-HT levels in the brain, they can indirectly stimulate all 14 serotonergic receptor subtypes [2,3], some of which are believed to lead to adverse side effects associated with these drugs. Common drugs for short-term relief of GAD are benzodiazepines. These sedating agents are controlled substances with addictive properties and can be lethal when used in combination with alcohol. The use of benzodiazepines is associated with addiction, dependency and cognitive impairment. 

Landen, M., Eriksson, E., Agren, H. and Fahlen, T. (1999) Effect of buspirone on sexual dysfunction in depressed patients treated with selective serotonin reuptake inhibitors. Journal of Clinical Psychopharmacology, 19, 268-271. 

There are numerous antidepressant medications on the market (table 7.1). Following development of monoamine oxidase (MAO) inhibitors were tricyclic antidepressants, selective serotonin reuptake inhibitors (SSRIs), and several atypical antidepressants (Baldessarini 1996). Successive generations of antidepressants have not necessarily become more effective in treating depression, but rather offer more favorable side-effect profiles—a crucial factor in effective clinical pharmacotherapy. An effective medication is not useful if its side effects are intolerable. 

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