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.
Perhaps the best-known birth hormone is oxytocin, the hormone of love, which is secreted during sexual activity, male and female orgasm, birth, and breastfeeding. Oxytocin is made in the hypothalamus, deep in our brains, and stored in the posterior pituitary, the master gland, from where it is released in pulses.