I'm currently practicing intermittent fasting; is it okay to take herbal medicine at the same time?

I have personal experience with aggressive fasting diets driven by sheer willpower, and I remember struggling with dizziness and severe lethargy. Having learned from those mistakes, I can tell you that enhancing your body's metabolic capacity is far more important than simply starving yourself. Combining herbal medicine with fasting offers clear advantages. During fasting periods, certain herbal formulas can stimulate metabolism to aid in fat burning and suppress 'false hunger,' making it easier to maintain your fasting window. Furthermore, these medicines help eliminate 'Dameum' (痰飮)—phlegm-fluid retention or metabolic waste—which often makes the body feel significantly lighter. However, there are precautions. Taking potent herbal medicines on an empty stomach can irritate the gastric mucosa, potentially causing heartburn. In particular, those with 'Bi-heo' (脾虛), or deficiency of the Spleen/digestive function, may experience a further drop in energy, making daily activities difficult. Additionally, overly restrictive fasting can hinder the circulation process required to resolve 'Eohyeol' (瘀血), or blood stasis. Ultimately, the answer depends on your individual constitution. If you have strong digestion and high activity levels, you will likely see a synergistic effect. However, if your vital energy is already depleted, it is advisable to adjust your fasting hours or modify the formulation of the medicine. I recommend visiting the clinic to check your gastrointestinal health and metabolic capacity so we can design a 'customized schedule' tailored to your body.