A nasal spray derived from pheromones, the airborne chemicals emitted by animals when trying to attract a mate, could soon be used to relief premenstrual syndrome.
Rather than making users attractive to the opposite sex though, early tests indicate that the spray, called PH80, banishes the blues and eases irritability, anxiety and physical symptoms such as bloating and breast pain. If planned studies go well, PH80 could be in pharmacies within the next few years, making it the first pheromone-based prescription medication.
"If this works, it would be very exciting and beneficial," says Ellen W. Freeman, a researcher at the University of Pennsylvania in Philadelphia who has tested PH80.
Antidepressants such as Prozac, which boosts levels of the mood-enhancing brain chemical, serotonin, are currently used to curb symptoms of PMS, and the more severe premenstrual dysphoric disorder. However, they can take a week or more to have an effect, and cause a loss of libido, anxiety and insomnia.
PH80, in contrast, could be used as needed. Preliminary studies of more than 100 women showed that their mood and physical symptoms rapidly improved after just a spritz of the spray. Larger tests must be conducted, however, before the product can be approved by the Food and Drug Administration.
PH80, which is a synthetic version of a chemical in human sweat, stimulates nerve endings in the vomeronasal organ, a tiny structure inside the nasal passages that is designed to detect pheromones. These nerve cells than send messages to the hypothalamus, a region of the brain that produces hormones that regulate mood, sex drive, anxiety, fear and appetite.
Scientists discovered the compound's ability to combat PMS quite by accident. In the early '90s, researchers tested the skin secretions on male and female volunteers simply to see if they sparked a reaction. After the study, about 70 of the women reported that their PMS symptoms had lifted.
"That opened up the possibility of studying the effect of these substances on PMS," says Dr. Louis Monti, a neuroscientist at Pherin Pharmaceuticals in Mountain View, Calif., who helped devise PH80. Still, researchers don't know exactly why this compound stops irritability and bloating. But brain scans indicate it activates the brain's "circuitry of emotions, the hypothalamus and limbic system, which correlates with a change in behavior," Monti says.
Unlike oral medications that are absorbed into the bloodstream through the digestive tract, PH80 works directly on the brain, so its effect is almost instantaneous. "Once you generate this electric signal, it travels to the brain in less than a second, compared to something you have to eat, which takes many orders of magnitude longer to have an effect," says Clive Jennings-White, a chemist at Pherin Pharmaceuticals.
Premenstrual syndrome is caused by the hormonal changes that occur in the two weeks before menstruation. Of the estimated 40 million women of childbearing age who experience PMS symptoms, more than 5 million suffer severe mood and behavioral symptoms, a condition known as premenstrual dysphoric disorder that often requires medical treatment.
Physical symptoms of PMS typically include headache, migraine, fluid retention, fatigue, painful joints, backache, abdominal cramping, breast tenderness, bloating, food cravings, heart palpitations and weight gain. Women may also experience dramatic mood swings, anxiety, depression, irritability, panic attacks and tension. Symptoms tend to taper off during menstruation, and sufferers usually remain symptom-free until the two weeks before their next menstrual period.
Studies have shown that 1,200 milligrams of calcium, taken daily, can reduce PMS symptoms -- as can regular exercise, even walking just 30 minutes a day. For women with more intense symptoms, doctors may prescribe antidepressants like Serafem (which is a variation of Prozac) or Zoloft.