> Intermittent fasting is any of various meal timing schedules that cycle between voluntary fasting (or reduced calorie intake) and non-fasting over a given period.[1][2] Methods of intermittent fasting include alternate-day fasting,[3] periodic fasting, such as the 5:2 diet, and daily time-restricted eating.[1][4]
Intermittent fasting is different than calorie restriction. There are calorie-restricted diets where you eat small amounts constantly throughout the day (this used to be the go-to recommendation of doctors). Intermittent fasting doesn't even necessarily entail calorie restriction.
Yes
> These drugs are chemically induced intermittent fasting.
No, they're a type of calorie restriction, as is intermittent fasting.