Constipation is complex and can have many causes but this might be a big and overlooked factor.
There is also a huge sleep connection here - see towards the bottom of the page!
Stop! Dose is important! Too much, as well as too little but there's no need to panic about this.
Yes, too much is bad but simply be careful to know what "too much" is. For context, there's 600mg of potassium in one glass of coconut water and how many kids drink at least that? Yes, the capsules only come in 99mg doses but if that was anything remotely close to a toxic amount then that simply wouldn't be allowed (the US FDA mandates 99mg maximum per cap). Imagine if two or three capsules was toxic. Do you think for a moment the FDA would have set the max at 99mg?
Here, we have never seen a result without giving at least 300mg and we now give 750mg in a pint of water, consumed over a couple of hours (so that's a glass and a half of coconut water equivalent). It's easy to get caught up in the idea that this is dangerous (I've done it myself!) but not dosing enough simply will not work. So, I want to deal with this up-front.
Confusingly, there are two different ways of measuring the dose of potassium. Getting them confused could be very bad indeed! When you buy a supplement you'll be seeing the amount of "elemental" potassium (how much actual potassium there is, as opposed to the weight of the supplement as a whole).
But when potassium is prescribed as a drug, the amount is measured in "mEq" ("milli equivalent"). To convert from mEq to a mg weight you have to know what the substance is. Since we know we're talking about potassium we can find the mEq conversion for potassium which is: 1 mEq = 39.1 mg.
So, a standard 20 mEq pharmaceutical dose of potassium is 782mg of elemental potassium (which happens to be exactly 8 X 99mg capsules).
For context, in a child, when doctors know that they may be about to have low potassium (hypokalemia) and they want to give it prophylactically (to prevent it), they dose 1-2 mEq up to 20 mEq at a time (so that's up to 8 caps at a time).
Many ASD kids have what’s referred to as “sluggish gut” which to me, sounds like ileus.
Wikipedia says: "Ileus is a disruption of the normal propulsive ability of the intestine due to the malfunction of peristalsis."
Most causes of Ileus are pretty esoteric except one: lack of potassium (hypokalemia).
From Wikipedia, on hypokalaemia:
"Symptoms may include feeling tired, leg cramps, weakness, and constipation.”
“Causes of hypokalemia include vomiting, diarrhea, medications like furosemide and steroids, dialysis, diabetes insipidus, hyperaldosteronism, hypomagnesemia, and not enough intake in the diet.”
“Hypokalemia is one of the most common water–electrolyte imbalances. It affects about 20% of people admitted to hospital.”
I’ve also seen mention of high-dose B vitamins lowering potassium (can’t recall the reference) and poor sleep also badly affects potassium levels (which sounds like a classic viscous cycle to me!).
We use Now Foods Potassium Citrate powder as it's the cheapest and easiest to dose (easiest - so watch your dosing!) but most forms are capsules of 99mg.
The US Adequate Intake for ages between 4 and 8 years is 2300 mg (that would be 23 standard capsules if getting it all from capsules and assumes they are not deficient!):
https://ods.od.nih.gov/factsheets/Potassium-HealthProfessional/
The Linus Pauling page on it says "Safety concerns with consuming potassium are limited in healthy people because the kidneys adjust urinary potassium excretion to potassium intake."
https://lpi.oregonstate.edu/mic/minerals/potassium
Under "Conditions that increase the risk of hypokalemia" it says (among other things):-
Prolonged vomiting or diarrhea
Overuse or abuse of laxatives
Magnesium depletion
Recovery from prolonged undernutrition
All of which could relate to pretty much any ASD kid.
They also mention "Oral doses of potassium >18 g taken at one time in individuals not accustomed to high intakes may lead to severe hyperkalemia"
18 grams is 180 caps in one go (or 10 teaspoons of Now Potassium Citrate = or three and a third tablespoons!). Even if the toxic dose was a quarter of that in a child, that's 45 caps in one go. (I am fairly sure it was that toxicity incident that was the driver for the US FDA to limit potassium supplement dosage to 99mg).
For context, there's 600 mg in a glass of coconut water and I'm sure many kids end up drinking more than that per day. There is also 600mg in a one small 5.5 fl oz (160 ml) can of Low Sodium V8 (I saw one parent on a Facebook group asking why giving it to his constipated daughter had made her poop within half an hour, ever day for the previous fortnight).
Note: If you're using a powder you obviously just need to be extra careful with dosing since you're using a measuring spoon not counting out capsules.
I wish I had a good answer.
I think this is probably sensible: Avoid giving single large doses (where large is much more than a glass of coconut water perhaps - 600 mg) and work up from lower (say 200 mg).
There may be a lot of room for larger doses over time (I saw somewhere reliable mention of large doses being problematic in those "not used to" potassium) but at the moment I have nothing to back that up and you really want to play it safe with any supplement, especially potassium.
We saw a big difference using 3 caps (300 mg) and have used up to 7.5 (750 mg) with big meals and water (which is still less than a glass of coconut water).
He pretty much went after every meal!
Note: This certainly is not the only answer to constipation. Constipation can have very many causes (probably several may be in play in one person) but this appears to be a badly overlooked one. (I must write something on constipation but: LifeExtension Mag Caps worked well. Oxy Powder for more serious constipation).
This has been one of the biggest game-changers we've ever found. Far less waking and far easier to return to sleep if he does.
I've come across the phrase "Magnesium for falling asleep. Potassium for staying asleep".
Potassium has been shown to reduce waking (sleep maintenance insomnia) and also make it easier to fall back to sleep:
This study showed earlier sleep onset and less daytime sleepiness (which suggests better quality sleep perhaps?):
Sleep Symptoms Associated with Intake of Specific Dietary Nutrients: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3866235/
And this study in male children says: “Potassium significantly increased actigraphic Sleep Efficiency (p less than 0.05) due to a reduction in actigraphic Wake after Sleep Onset (WASO) (p less than 0.05).”
Potassium affects actigraph-identified sleep: https://www.ncbi.nlm.nih.gov/m/pubmed/1947601/
Coconut water contains around 600 mg per cup: https://draxe.com/is-coconut-water-good-for-you/
This is interesting - relates Mag, sodium and potassium:
https://www.sassyholistics.com/2017/05/17/magnesium-sodium-and-potassium/
This mentions we need Vitamin A to retain potassium:
https://www.sassyholistics.com/2016/04/26/potassium-3/
Also: “If you were to look at a list of hypothyroid symptoms next to a list of potassium deficiency symptoms you’ll see how identical they are. We need potassium to make our cells more permeable for thyroid hormones!"