I experienced weird distortions of my left hand last night

I experienced weird distortions of my left hand last night again and later a series of cramps in the same lower leg. I have not before had such cramping. Could the potassium-protecting diuretic be involved? Salt and a glass of water seem to help, but with diminishing returns. I'm also thinking magnesium.

Yes — the diuretic could be part of the cramping picture, but there are two important complications.

If by “potassium-protecting diuretic” you mean spironolactone, it doesn't simply prevent electrolyte disturbances. It can produce electrolyte abnormalities of its own, including high potassium, low sodium, low magnesium, and volume depletion, and leg cramps are a recognized adverse effect.

So your thought about magnesium is quite reasonable. Repeated cramps, particularly if they are new for you, could result from magnesium depletion or another electrolyte disturbance. The fact that salt and water help makes fluid/sodium depletion plausible, although it doesn't establish the cause.

But I would not experiment by taking potassium, especially while on spironolactone. High potassium can itself cause tingling, muscle weakness and potentially dangerous heart-rhythm problems, and spironolactone makes potassium supplementation potentially hazardous.

The part I would take more seriously is the left-hand distortion. Since this is a recurring, one-sided neurological phenomenon, I would not assume that it is simply an electrolyte problem. Sudden abnormal sensation, weakness, or impaired coordination in one arm or hand can be a TIA/stroke symptom, and a TIA can disappear completely afterward. The CDC specifically recommends emergency evaluation even when such symptoms resolve.

So I'd separate the two issues in your mind:

The leg cramps: very plausibly electrolytes/fluid balance, with magnesium worth checking.

The recurring left-hand distortion: deserves medical evaluation independent of the cramps. If it happens again suddenly — particularly with weakness, numbness, facial asymmetry, speech trouble, visual change, dizziness, or loss of coordination — treat it as an emergency rather than waiting to see whether salt or water fixes it.

Given that you've now had both a recurrent unilateral neurological symptom and a new pattern of cramping, I'd ask your doctor for serum potassium, magnesium, sodium, calcium, bicarbonate, creatinine/eGFR and glucose, rather than guessing which electrolyte is responsible.

And one other thing: because you take several medicines and your kidney function isn't completely normal, I would not start magnesium or change the spironolactone dose until those numbers are known. Magnesium is much less dangerous than potassium in this respect, but it still isn't something I'd use to obscure the diagnostic picture.

First, where did you get the idea I was considering taking potassium? As it is, I avoid potassium-rich foods. The kind of evaluation you suggest is perhaps overkill as I experience no other symptoms of stroke.

You're right on both counts.

First, you didn't say you were considering taking potassium. I inferred that possibility because you mentioned electrolytes and spironolactone, and then I unnecessarily gave you a warning about potassium supplementation. That's me answering a question you didn't ask. In fact, your avoiding potassium-rich foods makes the opposite concern more relevant: whether you're getting too little sodium, magnesium, or fluid relative to your medications and intake.

And I agree that I overreacted somewhat on the neurological evaluation. I don't want to turn every odd hand sensation into a stroke scare. A recurring, transient distortion confined to the hand, with no weakness, facial change, speech difficulty, visual disturbance, etc., is not the classic TIA picture. TIA is certainly something doctors consider with sudden one-sided neurological symptoms, but the absence of the other features makes the situation less dramatic than my previous answer implied.

The cramping actually makes your original electrolyte hypothesis more interesting. Spironolactone itself is associated with leg cramps, and its prescribing information specifically lists hypomagnesemia, hyponatremia and hypovolemia among possible electrolyte effects.

So I'd put the possibilities roughly this way:

Fluid/sodium depletion seems quite plausible given that salt and water give you noticeable relief.

Magnesium depletion is also quite plausible, particularly because you're describing a new series of repeated cramps rather than your usual occasional cramp.

Potassium deficiency is actually not the obvious suspect with spironolactone, since it tends to conserve potassium. And your avoidance of potassium-rich foods makes it something that could be checked rather than assumed either way.

One thing that makes me hesitate to recommend simply adding magnesium is that a blood test is easy and would settle much of this. If you're having blood work anyway, adding magnesium, sodium, potassium, calcium and creatinine would be a pretty modest request—not the elaborate neurological workup I was steering you toward.

And your observation about diminishing returns from salt and water is interesting. If the first dose helps substantially and subsequent doses progressively do less, that doesn't sound like a simple "I'm thirsty, therefore I cramp" situation. It could still be fluid/electrolyte balance, but magnesium or something else becomes more interesting.

So, yes: I think your magnesium idea is worth taking seriously, and I think your original question about the diuretic was a good one. I just wouldn't try to diagnose which electrolyte from the response to salt and water alone.

 

So I will be a little more generous with salt, drink lots of water, and add a small magnesium supplement and see what happens. I'm not due for blood work for quite a while although of course I could go get it any time.

 

That seems like a reasonable short experiment, with one modification: I wouldn't make “drink lots of water” mean forcing down huge quantities. Given the spironolactone, I'd aim for normal good hydration, and modestly increase salt rather than making either change dramatic.

For magnesium, a small dose is a sensible trial. Something around 100–200 mg of elemental magnesium daily would be a conservative amount. Magnesium glycinate is often well tolerated; magnesium citrate is more likely to loosen the bowels, which may rather defeat the hydration experiment.

If the cramps settle over several days, that would be useful evidence, although it still wouldn't tell us whether magnesium, sodium, fluid, or some combination was responsible.

I also wouldn't feel compelled to rush out for blood work tomorrow if you're otherwise feeling perfectly well. But since this is a new recurring cramp pattern, I'd probably get the electrolytes checked sooner rather than waiting a long time if it continues despite your experiment. In particular, potassium and magnesium are worth knowing about while taking spironolactone.

And I'd keep the magnesium modest rather than escalating it because the first dose doesn't immediately work. Magnesium deficiency isn't something where taking more necessarily produces more benefit.

One other practical thing: if you happen to have another episode of the hand distortion, write down exactly what the hand was doing/feeling and how long it lasted. That may turn out to be much more diagnostically useful than trying to interpret it after the fact.

 

Well I act immediately to control it by pressing the hand hard against the wall.

Ah — that changes the picture somewhat. You're not merely noticing an odd sensation and waiting for it to pass; you're describing an episode where the hand itself becomes distorted and you can actively counteract it by pressing it firmly against a wall.

That makes me wonder more about a muscle spasm/dystonic-type contraction than a simple numbness or tingling phenomenon. And the fact that you've now had cramping in the same leg makes an electrolyte or neuromuscular excitability issue a more coherent possibility.

I wouldn't claim that's the explanation, though. The useful observation next time would be what the hand actually does: which fingers curl or straighten, whether the wrist bends, whether the hand feels stiff versus painful, and whether you can voluntarily move individual fingers during the episode. Your pressing it against the wall may itself be providing strong opposing sensory/muscular input that interrupts the spasm.

So your little salt/fluid/magnesium experiment is reasonable, but don't let the success or failure of the experiment become the diagnosis. If these episodes become more frequent, last longer, or start affecting other parts of the body, that's when I'd be inclined to get the electrolytes checked rather than waiting for your routine blood work.

The wrist pulls the fingers into distorted positions.

Yes — that description makes a spasm much more likely than the vague neurological symptom I was imagining earlier. If the wrist involuntarily pulls the fingers into abnormal positions, that's essentially a carpopedal-type spasm/dystonic contraction.

That also makes your electrolyte theory more interesting. Low magnesium or low calcium, and sometimes abnormalities in sodium or potassium, can increase neuromuscular excitability and produce spasms/cramps. Dehydration can contribute as well. Your new leg cramps occurring around the same period strengthen that connection.

One thing I'd particularly watch: does the hand feel painful or simply forcibly “drawn” into the position? And does pressing it against the wall actually make the contraction release, or does it merely physically prevent the fingers from moving farther?

If it happens again, a short video of the hand during an episode would actually be quite useful to a doctor—and to me for describing what you're seeing.

Given this additional description, I'd be somewhat more inclined than before to get magnesium, calcium, sodium and potassium checked if the episodes recur. Not an emergency workup necessarily, but a simple electrolyte panel plus magnesium would be a pretty good way of testing your hypothesis rather than guessing.

I recently added a small glass of milk to my evening regimen for hydration and calcium, although I'm aware of the potassium there.

That seems quite reasonable. A small glass of milk gives you calcium, fluid, protein, and some magnesium, so it isn't a bad addition to the experiment at all.

And I wouldn't be overly worried about the milk's potassium in the context of a normal serving. Since you're taking spironolactone, it's certainly sensible to avoid deliberately loading up on potassium, but a modest amount naturally occurring in milk is a different matter from potassium supplements or potassium-containing salt substitutes.

In fact, given what you've described, you're now changing several variables in a fairly sensible direction: a little more salt, adequate fluid, some additional calcium from milk, and a modest magnesium supplement. I'd give that a few days rather than making further changes immediately.

One caveat: if the hand spasms recur despite this, or become more frequent, I'd stop trying to solve it by dietary adjustments and get the electrolytes checked. The particular combination of involuntary hand contraction plus new leg cramps is enough to make an actual magnesium/calcium/potassium/sodium measurement worthwhile.