The poison is in the dose.
Never tried strychnine myself, of course, but there is history of using it as a stimulant and tonic, I have medical manuals from the late 1800s, granted they still reccomended using mercury and chalk as a baby teething powder, and their remedy for piles was to burn them off with HNO3, but strychnine isn't so bad, IF it is not in a toxic dose.
Too much water will kill through hyponatraemia, likewise, too much strychnine will drop you dead in a pretty godawful way, but less than a fatal dose, less still than a damaging dose, has indeed been used quite safely, medically.
Also, a strychnine containing seed (known as camalonga, by the curanderos who specialise in its use, although there is more than one plant known as camalonga) is used shamanically without lethality.
He did specifically inform that it was potentially lethal if too much was taken, warned of toxicity from lesser doses, then specifically specified a very low dose only, was to be potentially taken.
Quite different I personally believe, from advising morons to say, test to see if a DMSO solution of KCN was hot enough.
At those sorts of doses, I would be interested to try strychnine actually, or perhaps the less toxic brucine.
A small dose of gelsemium tincture (gelsemine is a glycine agonist, although toxic in larger doses than should be taken) would reverse toxic effects if need be, in an emergency or if severe, although that too is a potentially lethal paralytic agent if too much is used, glycine also would likely help ameliorate milder side effects, since strychnine is a glycine receptor antagonist, and I believe although high affinity, it is competitive (I.e an allosteric blocker)
Strychnine IS a notorious poison, but the dose alone make it so, like I say, too much water and you die, and I myself have taken up to 3-4 mg of huperzine-A, if I had taken that the first time I took it, given a starting active dose is 50-100 micrograms I would have been quite seriously ill, it is a cholinesterase inhibitor, a nerve agent, just like sarin or VX, or carbamate insecticides, although unlike those, reversible, yet after becoming used to it, and ramping up the dose slowly, I didn't die, I did not experience lachrymatory effects, nor nausea or the shits, or sweating, all I noticed, in the way of side effects were upon the pupil of the eye, and a slight to moderate lowering of the heart rate, whilst getting the cognitive boost and reversal of memory loss that I was wanting out of its use.
Act like a moron around a potent neurotoxin, you will get fucked in the arse with a sharp stick, act with respect and you will not, short of tragic accidents, just look at that guy who dipped his tongue in a baggie of 2C-T-7 (or it might have been 2C-T-4 I do not remember) instead of weighing a dose, what happened? the guy died, or that poor bastard who railed a whomping line of DOB in mistake for MDxx, again, he got fucked.