Of course, one of the reasons for that in my case is because I never did buy into the idea that giving a healing herb an "instantaneous effect" made all its problems go away. On the contrary, it made all the biochemical price of using that herb come due all at once, just like the effects take place all at once. "Makes the effect instantaneous" to me meant "speeds up the process until it's too fast to consciously register."
Practical effects of this attitude:
1. If you're going to take nearly any kind of instantaneous herb, you should probably drink water until you're practically sloshing out your ears before you take it. Depending on the herb, you might have to roll system shock to keep from dying of dehydration if you fail to do this. Almost anything animal bodies use, up to and including oxygen, use up water in the process of performing their functions.
1a. Because of the above, most instantaneous herbs are not suitable for use on unconscious patients.
2. Many "healing" herbs not only provide fuel for recovery and or/tweaks to blood chemistry to alter the healing process, they purge the system of unwanted substances. Note that it's just an herb, the only avenues it has for this are those inherent in the patient's biology, such as respiration, perspiration, urination and defecation, vomiting, etc. If "the effects are instantaneous" in any herb with purgative qualities, the avenues it uses for those functions are likewise instantaneous. In other words, you might want to take off the patient's clothes before administering the herb, and he'll probably want a bath afterwards. For that matter, anyone who stood too close to him when he took it might want a bath as well.
2a. Due to the above, an animal that can track you by scent for a day will be able to spot the place where you took that healing herb a lot longer than a day later.
3. Unless the herbal mixture in question also contains items for recovery (healing generates its own forms of fatigue poisons, no? And it also certainly uses up a lot of a body's fuel reserves) then once the effect takes place the patient will likely have to make some sort of Constitution RR in order to remain conscious. So now you have a patient who's healthy.... just starving.