Why progesterone causes mood changes
Jan. 26th, 2010 at 8:02 AM
The brain has both estrogen and progesterone receptors. In women who have epilepsy, seizures are known to occur more frequently during times of high estrogen (late follicular phase and ovulation) and they are decreased when progesterone is high. In this sense, progesterone acts a a brain anesthetic to some degree. High doses of progesterone can be very sedating.
Women who have depression, have lower brain levels of serotonin, thus the success of medications that block the body’s degradation of serotonin and allow brain levels to remain higher. Estrogens are known to block one of the enzymes (monoamine oxidase – MAO) which degrades serotonin with the result of elevating mood. Progestogens, probably more so than natural progesterone, increase MAO concentration thus producing depression and irritability. Pure progestogen treatment without estrogen, such as DepoProvera® is know to worsen depression in women who already have a tendency toward or clinical signs of depression.