Hello Lisagarmaise, Serotonin is to blame! Excessive release of 5HT(serotonin) from intestinal mucosa cells can cause diarrhea and nausea. Metformin stimulates these intestinal cells to produce increased levels of 5HT, as soon as 10-15 minutes after taking metformin. The good news is that most symptoms dissapear after taking metformin for 2-3 weeks.
Progesterone, hormone secreted by the female reproductive system that functions mainly to regulate the condition of the inner lining (endometrium) of the uterus. Progesterone is produced by the ovaries, placenta, and adrenal glands.
(January 2010) Endocrine glands are glands of the endocrine system that secrete their products, hormones, directly into the blood rather than through a duct. The major glands of the endocrine system include the pineal gland, pituitary gland, pancreas, ovaries, testes, thyroid gland, parathyroid gland, hypothalamus and adrenal glands.