Venlafaxine and ecchymosis

A Hematoma in the Anterior Abdominal Muscle in a Woman Receiving Venlafaxine: A Literature Review of the Reports on Similar Cases

INTRODUCTION

Venlafaxine (VEN) is a selective norepinephrine reuptake inhibitor (SNRI) that mainly helps treat major depressive disorder and anxiety and panic disorders. It works by inhibiting the reuptake of serotonin (5-hydroxytryptamine, 5-HT) and noradrenaline (NA) by presynaptic neurons. Additionally, VEN administration has been linked with a bleeding predisposition that may be due to the inhibition of NA and 5-HT uptake by platelets which have their own receptors on their surface and are implicated in platelet aggregation.

CASE PRESENTATION

Herein, we report a case of a 54-year-old patient treated with VEN, who presented with a hematoma in the anterior abdominal muscle. We also present the observational studies and case reports highlighting the association of SNRIs use with various hemorrhagic complications ranging from gastrointestinal hemorrhage or vaginal bleeding to bleeding during or after surgery due to either thrombocytopenia or impaired platelet aggregation.

CONCLUSION

Given the cases of either reductions in the platelet count or impairment of platelet activity accompanied by bleeding events, every clinician should be aware of these possible adverse effects when prescribing SNRIs.

Effects of selective serotonin reuptake inhibitors on platelet function: mechanisms, clinical outcomes and implications for use in elderly patients

Among the antidepressants, the selective serotonin reuptake inhibitors (SSRIs) are often preferred to other classes of antidepressants in the treatment of depression in the elderly because of their better safety profile. Most of the known effects of SSRIs, either beneficial or adverse, are linked to their inhibitory action on the serotonin reuptake transporter (5-HTT). This reuptake mechanism is present not only in neurons but also in other cells such as platelets. Serotoninergic mechanisms seem to play an important role in haemostasis, and their importance in this regard has long been underestimated. Abnormal activation may lead to a pro-thrombotic state, as may occur in patients with major depressive disorder, whilst downregulation, as occurs in patients treated with SSRIs, may have two clinical consequences, both of particular interest in the elderly. On the one hand, there may be an increased risk of bleeding; on the other hand, a reduction in thrombotic risk may be possible. Polymorphism in the promoter region of the gene that transcribes the 5-HTT has been shown to have a relevant impact on its function and, in turn, on the beneficial and adverse effects of SSRIs. Bleeding has been a concern since the introduction of SSRIs, with multiple case reports published and communicated to the pharmacovigilance systems. The first epidemiological study was published in 1999 and since then, 34 epidemiological studies from different areas, most of them including elderly patients in their study populations, have been published with a variety of results. Broadly, the epidemiological evidence supports a moderately increased risk of bleeding associated with the use of SSRIs, which may be critically dependent on patient susceptibility and the presence of risk factors. The impairment of primary haemostasis induced by SSRIs may result, as a beneficial counterpart, in a reduction in the thrombotic risk. A small number of clinical trials and an increasing number of epidemiological studies that include elderly patients have been conducted to clarify whether SSRIs reduce the risk of primary and secondary ischaemic disorders. However, the results have been inconclusive with some studies suggesting a preventive effect and others no effect or even an increased risk. Behind such contradictory results may be the role of depression itself as a cardiovascular risk factor and, therefore, a major confounding factor. How to disentangle its effect from that of the antidepressants is the methodological challenge to be overcome in future studies. In this complex scenario, the elderly seem to be at a crossroads, because they are the group in which both the risks and the benefits can be the greatest. Studies performed to date have provided us with some clues that can help orient clinicians in taking the most appropriate course of action. For instance, as the gastrointestinal bleeding risk appears to increase with age, prudent advice in patients with a previous history of upper-gastrointestinal bleeding or peptic ulcer, and in those who take NSAIDs, oral anticoagulants, antiplatelet drugs or corticosteroids, would be to suggest addition of an acid-suppressing agent to the drug regimen in those elderly patients in whom SSRIs are indicated.

Ecchymoses as an adverse effect of fluoxetine treatment

We report a case of a 28-year-old major depressive female patient who manifested ecchymoses following fluoxetine use. After substitution of sertraline, her depression resolved after 4 weeks and ecchymoses 1.5 months latter. This is an unexplored side-effect with unknown long-term consequences that warrants further study.

Influence of antidepressants on hemostasis

Antidepressants, particularly selective serotonin reuptake inhibitors (SSRIs), are widely used for the treatment of depression and anxious disorders. The observation that depression is an independent risk factor for cardiovascular mortality and morbidity in patients with ischemic heart disease, the assessment of the central role of serotonin in pathophysiological mechanisms of depression, and reports of cases of abnormal bleeding associated with antidepressant therapy have led to investigations of the influence of antidepressants on hemostasis markers. In this review, we summarize data regarding modifications of these markers, drawn from clinical studies and case reports. We observed an association between the type of antidepressant drug and the number of abnormal bleeding case reports, with or without modifications of hemostasis markers. Drugs with the highest degree of serotonin reuptake inhibition - fluoxetine, paroxetine, and sertraline - are more frequently associated with abnormal bleeding and modifications of hemostasis markers. The most frequent hemostatic abnormalities are decreased platelet aggregability and activity, and prolongation of bleeding time. Patients with a history of coagulation disorders, especially suspected or documented thrombocytopenia or platelet disorder, should be monitored in case of prescription of any serotonin reuptake inhibitor (SRI). Platelet dysfunction, coagulation disorder, and von Willebrand disease should be sought in any case of abnormal bleeding occurring during treatment with an SRI. Also, a non-SSRI antidepressant should be favored over an SSRI or an SRI in such a context. Considering the difficulty in performing platelet aggregation tests, which are the most sensitive in SRI-associated bleeding, and the low sensitivity of hemostasis tests when performed in case of uncomplicated bleeding in the general population, establishing guidelines for the assessment of SRI-associated bleeding complications remains a challenge.

Antidepressants and risk of upper gastrointestinal bleeding

Selective serotonin reuptake inhibitors (SSRIs) are nowadays the most widely used antidepressants in the world, mainly because they have a better adverse reaction profile and a higher safety margin in overdoses, when compared to other antidepressants. These drugs recently have been the target of important debates concerning safety issues, among them the possibility that they may increase the risk of bleeding. Over the 1990s, an increasing number of individual cases of bleeding disorders were reported in the literature and to the pharmacovigilance programmes which prompted several epidemiological and pharmacological studies. In this review we have examined all available data. The whole evidence supports the hypothesis that antidepressants with a relevant blockade action on serotonin reuptake mechanism increase the risk of bleeding. Such disorders may have different degrees of severity and may be located anywhere in the body. The epidemiological evidence is, however, more robust for upper gastrointestinal bleeding. It has been estimated that upper gastrointestinal bleeding may occur at a frequency ranging from 1 in 100 to 1 in 1,000 patient-years of exposure to high-affinity drugs (the SSRIs), with the very old patients being in the highest part of the range. The increased risk may be of particular relevance when the SSRIs are associated with NSAIDs as well as low-dose aspirin.

Venlafaxine-induced ecchymoses and impaired platelet aggregation

OBJECTIVE

To describe a case of venlafaxine-induced ecchymoses.

METHODS

A patient with a history of ecchymoses coincident with venlafaxine therapy was rechallenged with the drug. Her platelet function was assessed with aggregation and ATP release studies before the rechallenge and after she developed ecchymoses. In addition, the effect of venlafaxine on platelet aggregation and ATP release was studied in vitro by adding the drug to platelet-rich plasma from normal donors.

RESULTS

After 4 wk of treatment with venlafaxine our patient developed extensive ecchymoses. At that time her platelet aggregation and release responses to epinephrine, ADP, collagen, and arachidonic acid were markedly suppressed. Adding venlafaxine to normal platelet-rich plasma also dramatically reduced the aggregation and release responses to the same agonists as well as to serotonin, but the concentrations of venlafaxine required were 1000-fold greater than those normally achieved clinically.

CONCLUSIONS

Our patient demonstrated an idiosyncratic hypersensitivity to the platelet inhibitory effects of venlafaxine. Because venlafaxine is an inhibitor of serotonin uptake by platelets and neurons, this mechanism may contribute to the impact of this drug on platelet function. However, our in vitro studies suggest that this hypothesis is inadequate to explain the observations completely.

Selective serotonin reuptake inhibitors and increased bleeding risk: are we missing something?

PURPOSE

Selective serotonin reuptake inhibitors (SSRIs) are first line agents to treat clinical depression. Although these medications exhibit a favorable safety profile, there are multiple case reports, registries, and uncontrolled studies suggesting that use of SSRIs might be associated in the increased risk of bleeding events. There is also emerging evidence that these side effects of SSRIs are due to blockade of serotonin reuptake in platelets and subsequent platelet dysfunction.

METHODS

The analysis of evidence linking SSRIs with bleeding episodes to define the prevalence, specific clinical characteristics, and estimated risk when SSRIs are used in combination with antiplatelet agents or/and anticoagulants.

RESULTS

There are over 120 MEDLINE-cited peer-reviewed research papers and more than 50000 Web pages devoted to SSRI-related bleeding events.

CONCLUSION

Independently of the brand, use of SSRIs is indeed associated with increased bleeding risk. Although such complications are rare, their frequency is growing, and physicians should be aware of SSRI-induced hemorrhages, especially in patients with hereditary platelet defects, and those treated with antiplatelet agents. Prospective studies are urgently needed to determine whether SSRIs will yield additional bleeding risks when used long term concomitantly with aspirin or clopidogrel.

Selective serotonin re-uptake inhibitors and the risk of bleeding

Despite their safety, selective serotonin re-uptake inhibitors (SSRIs) are associated with bleeding. The authors critically reviewed the medical literature on SSRIs to identify subgroups of patients at risk of bleeding complications. The authors performed a literature search using MEDLINE from 1966 to 1st September 2004 using; 'haemorrhage, serotonin uptake inhibitors and antidepressive agents' as search terms and followed up on citations in each paper that was relevant to SSRI associated bleeding. The authors reviewed 7 retrospective analytical studies and 24 case reports of bleeding in 43 different people. Analytical studies support an association between SSRI consumption and upper gastrointestinal (GI) bleeding and perioperative bleeding. Little evidence links SSRI use with intracerebral haemorrhage. The risk of GI bleeding appeared to be highest among patients consuming SSRIs with NSAIDs. Combining aspirin or NSAIDs with SSRIs may further increase the risk of bleeding. Clinicians should caution patients about combining SSRIs with aspirin or NSAIDs. Pharmacotherapy to reduce the risk of GI bleeding should be considered in high risk patients.