Antidepressants are sometimes used to treat PMS, but how much help a woman might get depends on her specific symptoms, a US study said.
Researchers at the University of Pennsylvania found that of 447 women in clinical trials testing sertraline (Zoloft) for PMS, those with "mixed" symptoms - multiple physical and psychological symptoms - were the most likely to see an improvement.
In contrast, women with mainly physical PMS symptoms got little help, unless they had severe bloating or breast tenderness, the researchers said in the journal Obstetrics & Gynecology.
"There's an enormous range of PMS symptoms, and an enormous range in how severe they are," said Ellen Freeman, a research professor of obstetrics and gynaecology at the University of Pennsylvania in Philadelphia.
Symptoms of PMS
Many women have symptoms like bloating, breast tenderness, headache and emotional stress shortly before their menstrual periods. Often, simple fixes such as diet changes, exercise and over-the-counter painkillers are enough to manage the symptoms.
But for some, PMS is severe enough to disrupt their daily lives, and antidepressants known as selective serotonin re-uptake inhibitors (SSRIs) may be prescribed.
Studies have found that antidepressants can help some women with PMS or premenstrual dysphoric disorder (PMDD), a severe form of PMS thought to affect a small percentage of women.
But about 40% of women who try an SSRI do not see a benefit.
Freeman, who has received funding from antidepressant manufacturers, noted that no SSRI is approved for treating PMS, but doctors are allowed to prescribe the medications for PMS symptoms and clinical trials have included women with both severe PMS and the more severe PMDD.
Freeman's team focused on 447 women with PMS or PMDD who were randomly assigned to take either sertraline or an inactive placebo. The majority had the "mixed" subtype of PMS and PMDD, with significant physical and psychological symptoms.
Almost two-thirds reported a 50% improvement in their symptoms over three menstrual cycles, compared with 42% of the women getting the placebo.
But the antidepressant was less effective for women with primarily physical symptoms.
"They physical symptoms seemed truly not to respond, unless they were severe breast tenderness or bloating," Freeman said.
She noted that the study only looked at sertraline, so it's not possible to say for sure whether the findings would be true for other SSRIs, though that was likely to be the case.
She added that as with any drug, a woman would have to balance the possible benefits of treatment with an SSRI against the risk of side effects.
One of Freeman's colleagues on the study has received research funding from Pfizer Inc, which markets Zoloft. Freeman has received funding from several other drugmakers.
(Reuters, December 2011)