What is the proper way to brew senna?

There are many correct brewing methods of senna, the common is to use 200 ml of boiling water to brew 2~3 grams, the 2nd time with 150 ml of water to brew again.
Senna leaves taste sweet, bitter, cold, to the large intestine meridian, with diarrhea heat stagnation, laxative, diuretic effect. It is used for heat stagnation (the accumulation of dry heat in the spleen, stomach and large intestine, resulting in transport and conduction disorders), constipation and abdominal pain, edema and other conditions.
First boil the water, about 200 ml of water to brew 2-3 grams of senna, about 25 minutes, cool and then drink. The second time with 150 milliliters of boiling water once again.
An overdose of senna may cause diarrhea. It should not be taken by women during menstruation, pregnancy, breastfeeding, or those with high blood pressure. Adverse effects are not known.
Patients are advised to seek medical attention if they feel unwell. It is recommended to take Senna under the guidance of a physician and not to take the drug on your own to avoid adverse reactions.