Thanks, you got me to get up and read on the topic. Unfortunately, it appears that yes, amphetamines have indeed been observed to have some interaction with the kidneys. In case you're anxious, be aware that kidney sensations are indeed somewhat commonly reported.
Here's just two examples (of many) from another site relating a similar concern:
"I tried the 30 mg dosage for one day, and I got a weird sensation around my kidneys, like they were working overtime. Anyone else run acroos this, or know what effect Adderall
has on kidney function?"
"My lower back aches, and it feels like my kidneys are being over worked.
I've been having kidney stones periodically since i was 17 years old. But never felt like this from adderall. I'm starting to wonder if my kidney problems are result from the adderall?"
In another thread, guaifenesin was suggested as a possible remedy for the sensation, though I can't attest to it's efficacy. Individuals in the thread seem pretty supportive, however.
Attached is an article of a man admitted to a hospital due to acute kidney failure following injection of amphetamines. Of course, this isn't a very good comparison; injected amphetamines are quite a different experience compared to orally ingested amphetamines in Adderall. However, the researchers highlight that twelve cases of acute renal failure induced by amphetamine
have been reported. Their primary suggestion is acute tubular necrosis - but they also suggest that the vasoconstrictive properties of amphetamines may also contribute. Whatever the specific cause, there is clearly some cellular stress-related interaction.
Given the described situation, and the admirable caution taken with one's physiology - I don't think that the described individual is in any danger of kidney failure. However, the fact that one is being over-worked and stressed, coupled with the upped dosages and consequential neurochemical changes that are associated with amphetamines, is cause for some calm
concern. If it persists, having a conversation with your doctor might be in order.
After reading through some of the information that I found, it seems that the regular ingestion of pedialyte might actually be significant here, and counterintuitively counterproductive. It may be preferable to ingest water alone, without any electrolytes or vitamins. I'm not very familiar with kidney function, but I would imagine that prolonged heightened concentrations of such compounds would force the kidneys to function to filter the blood at a higher rate - while the kidneys are already being recruited by the upped amphetamine dosage. Since amphetamines dehydrate the body, and decrease the concentrations of water in the body - it wouldn't surprise me that an overly nutrient-dense, hypertonic environment might be produced for the kidneys. Over a prolonged period of time, this might 'over-work' the kidneys. I'm not sure, however, that pedialyte has significant levels of dissolved compounds.
Thanks for your question, I learned alot! Hope this helps, and good luck!