Hormonal Venlafaxine

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. 

SSRIs are theorized to reduce the frequency of hot flashes by increasing serotonin in the central nervous system and by decreasing LH. Of the SSRIs, citalopram, paroxetine, and sertraline all have been studied and have demonstrated a reduction in hot flashes while treating other symptomatic complaints such as depression and anxiety.33 Venlafaxine, which blocks the reuptake of serotonin and norepinephrine, has demonstrated a reduction in hot flashes primarily in the oncology population.34 Overall, these antidepressant medications offer a reasonable option for women who are unwilling or cannot take hormonal therapies, particularly those who suffer from depression or anxiety. These agents should be prescribed at the lowest effective dose to treat symptoms and may be titrated based on individual response. 

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. 

Hyponatremia Hyponatremia and the syndrome of inappropriate antidiuretic hormone secretion (SIADH) may occur with venlafaxine. 

There have been other reports of hyponatremia with SSRIs (38,39). Hyponatremia is probably more common with SSRIs than with tricyclic antidepressants and predominantly but not exclusively affects older patients. Most reports involve fluoxetine, but this might represent greater patient exposure. All SSRIs and venlafaxine can produce this adverse effect (SEDA-23,21 SEDA-25,14). According to published reports, the median time to the onset of hyponatremia is 13 days (range 3-120) and the presentation is of inappropriate secretion of antidiuretic hormone (38). Symptoms, such as lethargy and confusion, can be non-specific, so awareness of the possibility of SSRI-induced hyponatremia, particularly in elderly people, is needed. 

FIGURE 3.2. Protocol for thr STARED project, (a) Level 1 (b) level 2 (c) level 3 (d) level 4. CIT, citalopram SER, sertraline BUP, bupropion VEN, venlafaxine CT, cognitive-behavioral therapy BUS, Buspirone MIRT, mirtazpine NTP, nortriptyline LI, lithium THY, thyroid hormone TCP, tranylcypromine. 

But breast cancer survivors tend to have lots of hot flashes, about thirty-five per week, says Maki. The sudden depletion of hormones blindsides your internal thermostat. Skin flushes, sweating, perhaps even palpitations, nausea and dizziness, are the body s valiant attempt to regulate itself. They are terrible and persistent, affecting sleep and quality of life, she says. If a healthy woman without breast cancer takes estrogen, it basically cures her of hot flashes. But a woman undergoing treatment for breast cancer does not have a choice in terms of therapy because she can t take estrogen. Some patients find the antidepressant venlafaxine helpful." ... 

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