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Showing posts with label Furosemide. Show all posts
Showing posts with label Furosemide. Show all posts

Tuesday 14 May 2019

Making best use of existing NKCC1/2 Blockers in Autism






Azosemide C12H11ClN6O2S2  


Today’s post may be of interest to those already using bumetanide for autism and for those considering doing so.  It does go into the details, because they really do matter and does assume some prior knowledge from earlier posts.

There has been a very thorough new paper published by a group at Johns Hopkins:-
It does cover all the usual issues and raises some points that have not been covered yet in this blog.  One point is treating autism prenatally. This issue was studied twice in rats, and the recent study was sent to me by Dr Ben Ari.  Short term treatment during pregnancy produced a permanent benefit.

Maternal bumetanide treatment prevents the overgrowth in the VPA condition

            
Brief maternal administration of bumetanide before birth restores low neuronal intracellular chloride concentration ([Cl]i) levels, produces an excitatory-to-inhibitory shift in the action of γ-aminobutyric acid (GABA), and attenuates the severity of electrical and behavioral features of ASD (9, 10), suggesting that [Cl]i levels during birth might play an important role in the pathogenesis of ASD (7). Here, the same bumetanide treatment significantly reduced the hippocampal and neocortical volumes of P0 VPA pups, abolishing the volume increase observed during birth in the VPA condition [hippocampus: P0 VPA versus P0 VPA + BUM (P = 0.0116); neocortex: P0 VPA versus P0 VPA + BUM (P = 0.0242); KWD] (Fig. 3B). Maternal bumetanide treatment also shifted the distribution of cerebral volumes from lognormal back to normal in the population of VPA brains, restoring smaller cerebral structure volumes (Fig. 3C). It also decreased the CA3 volume to CTL level after birth, suggesting that the increased growth observed in this region could be mediated by the excitatory actions of GABA (Fig. 3D). Therefore, maternal bumetanide administration prevents the enhanced growth observed in VPA animals during birth.

One issue with Bumetanide is that it affects both:-

·        NKCC2 in your kidneys, causing diuresis
·        NKCC1 in your brain and elsewhere, which is divided into two slightly different forms NKCC1a and NKCC1b

NKCC1 is also expressed in your inner ear where it is necessary for establishing the potassium-rich endolymph that bathes part of the cochlea, an organ necessary for hearing. 

If you block NKCC1 too much you will affect hearing.

Blocking NKCC1 in children and adults is seen as safe but the paper does query what the effect on hearing might be if given prenatally as the ear is developing.

Treating Down Syndrome Prenatally

While treating autism prenatally might seem a bit unlikely, treating Down Syndrome (DS) prenatally certainly is not.  Very often DS is accurately diagnosed before birth creating a valuable treatment window.  In most countries the vast majority of DS prenatal diagnoses lead to termination, but only a small percentage of pregnancies are tested for DS. In some countries such as Ireland a significant number of DS pregnancies are not terminated, these could be treated to reduce the deficits that will otherwise inevitably follow.



The research does suggest that DS is another brain disorder that responds to bumetanide.


Back to autism and NKCC1

This should remind us that a defect in NKCC1 expression will not only cause elevated levels of chloride with in neurons, but will also affect the levels of sodium and potassium with neurons.

There are many ion channel dysfunctions (channelopathies) implicated in autism and elevated levels of sodium and potassium will affect numerous ion channels.  The paper does suggest that the benefit of bumetanide may go beyond modifying the effect of GABA, which is the beneficial mode of action put forward by Dr Ben Ari.
We have seen how hypokalemic sensory overload looks very similar to what often occurs in autism and that autistic sensory overload is reduced by taking an oral potassium supplement.

The paper also reminds us that loop diuretics like bumetanide and furosemide not only reduce inflow of chloride into neurons, but may also reduce the outflow. This is particularly known of furosemide, but also occurs with bumetanide at higher doses.
The chart below shows that the higher the concentration of bumetanide the strong its effect becomes on blocking NKCC1.


But at higher doses there will also be a counter effect of closing the NKCC2 transporter that allows chloride to leave neurons.
At some point a higher dose of bumetanide may have a detrimental effect on trying to lower chloride within neurons.

Since Dr Ben Ari’s objective is to lower chloride levels in neurons  it is important how freely these ions both enter and exit.  The net effect is what matters. (Loop diuretics block NKCC1 that lets chloride enter neurons but also block the KCC2 transporter via which they exit)

Is Bumetanide the optimal existing drug to lower chloride within neurons?  Everyone agrees that it is not, because only a tiny amount crosses into the brain. The paper gives details of the prodrugs like BUM5 that have been looked at previously in this blog; these are modified versions of bumetanide that can better slip across the blood brain barrier and then react in the brain to produce bumetanide itself.  It also highlights the recent research that suggests that Bumetanide may not be the most potent approved drug, it is quite conceivable that another old drug called Azosemide is superior.

The blood brain barrier is the problem, as is often the case.  Bumetanide has a low pH (it is acidic) which hinders its diffusion across the barrier.  Only about 1% passes through.

There is scepticism among researchers that enough bumetanide can cross into the brain to actually do any good.  This is reflected in the review paper.

The paper reminds us of the research showing how you can boost the level of bumetanide in the brain by adding Probenecid, an OAT3 inhibitor.  During World War 2 antibiotics were in short supply and so smaller doses were used, but their effect was boosted by adding Probenecid. By blocking OAT3, certain types of drug like penicillin and bumetanide are excreted at a slower rate and so the net level in blood increases.

The effect of adding Probenecid, or another less potent OAT3 inhibitors, is really no different to just increasing the dose of bumetanide.

The problem with increasing the dose of bumetanide is that via its effect on NKCC2 you cause even more diuresis, until eventually a plateau is reached.

Eventually, drugs selective for NKCC1a and/or NKCC1b will appear.

In the meantime, the prodrug BUM5 looks good. It crosses the BBB much better than bumetanide, but it still affects NKCC2 and so will cause diuresis.  But BUM5 should be better than Bumetanide + Probenecid, or a higher dose of Bumetanide.  BUM5 remains a custom-made research drug, never used in humans.

I must say that what again stands out to me is the old German drug, Azosemide.

In a study previously highlighted in this blog, we saw that Azosemide is 4 times more potent than Bumetanide at blocking NKCC1a and NKCC1b.

Azosemide is more potent than bumetanide and various other loop diuretics to inhibit the sodium-potassium-chloride-cotransporter human variants hNKCC1A and hNKCC1B

Azosemide is used in Japan, where recent research shows it is actually more effective than other diuretics

Azosemide, a Long-acting Loop Diuretic, is Superior to Furosemide in Prevention of Cardiovascular Death in Heart Failure Patients Without Beta-blockade 

As is often the case, Japanese medicine has taken a different course to Western medicine.

Years of safety information has already been accumulated on Azosemide.  It is not an untried research drug. It was brought to market in 1981 in Germany. It is available as Diart in Japan made by Sanwa Kagaku Kenkyusho and as a cheaper generic version by Choseido Pharmaceutical. In South Korea Azosemide is marketed as Uretin.


In any other sector other than medicine, somebody would have thought to check by now if Azosemide is better than Bumetanide.  It is not a matter of patents, Ben-Ari has patented all of the possible drugs, including Azosemide and of course Bumetanide.

So now we move on to Azosemide.



When researchers came to check the potency of the above drugs the results came as a surprise.  It turns out that the old German drug Azosemide is 4 times as potent as bumetanide.






The big question is how does it cross the blood brain barrier.


“The low brain concentrations of bumetanide obtained after systemic administration are thought to result from its high ionization (>99%) at physiological pH and its high plasma protein binding (>95%), which restrict brain entry by passive diffusion, as well as active efflux transport at the blood-brain barrier(BBB). The poor brain penetration of bumetanide is a likely explanation for its controversial efficacy in the treatment of brain diseases

“… azosemide was more potent than any other diuretic, including bumetanide, to inhibit the two NKCC1 variants. The latter finding is particularly interesting because, in contrast to bumetanide, which is a relatively strong acid (pKa = 3.6), azosemide is not acidic (pKa = 7.38), which should favor its tissue distribution by passive diffusion. Lipophilicity (logP) of the two drugs is in the same range (2.38 for azosemide vs. 2.7 for bumetanide). Furthermore, azosemide has a longer duration of action than bumetanide, which results in superior clinical efficacy26 and may be an important advantage for treatment of brain diseases with abnormal cellular chloride homeostasis.”


Dosage equivalents of loop Diuretics


Bumetanide has very high oral bioavailablity, meaning almost all of what you swallow as a pill makes it into your bloodstream.

Furosemide and Azosemide have much lower bioavailability and so higher doses are needed to give the same effect.

Both Furosemide and Bumetanide are short acting, while Azosemide is long acting.

For a drug that needs to cross the blood brain barrier small differences might translate into profoundly different effects.

The limiting factor in all these drugs is their effect on NKCC2 that causes diuresis.

1mg of bumetanide is equivalent to 40mg of furosemide.
2mg of bumetanide is equivalent to 80mg of furosemide.

The standard dose for Azosemide in Japan, where people are smaller than in the West, is 30 mg or 60mg. 

Research suggests that the same concentration of Azosemide is 4x more potent than Bumetanide at blocking NKCC1 transporters, other factors that matter include:-

·        How much of the oral tablet ends up in the bloodstream.
·        How long does it stay in the blood stream
·        How much of the drug actually crosses the blood brain barrier
·        How does the drug bind to the NKCC1 transporters in neurons
·        How rapidly is the drug excreted from the brain
·        What effect is there on the KCC2 transporter that controls the exit of chloride ions from neurons.

All of this comes down to which is more effective in adults with autism 2mg of bumetanide or 60mg of Azosemide.

The side effects, which are mainly diuresis and loss of electrolytes will be similar, but Azosemide is a longer acting drug and so there will be differences. In fact Azosemide is claimed to be less troublesome than Bumetanide in lower potassium levels in your blood.

Conclusion  

The open question is whether generic Azosemide is “better” than generic Bumetanide for treating brain disorders in humans.

I did recently ask Dr Ben-Ari if he is aware of any data on this subject. There is none.

Many millions of dollars/euros are being spent getting Bumetanide approved for autism, so it would be a pity if Azosemide turns out to be better. (Dr Ben Ari’s company Neurochlore wants to develop a new molecule that will cross the blood brain barrier, block NKCC1 and not NKCC2 and so will not cause diuresis).

The hunch of the researchers from Hanover, Germany seems to be that the old German drug Azosemide will be better than Bumetanide.

I wonder if doctors at Johns Hopkins / Kennedy Krieger have started to prescribe bumetanide off-label to their patients with autism.  Their paper shows that they have a very comprehensive knowledge of the subject.


===========

I suggest readers consult the full version of the Johns Hopkins review paper on Bumetanide, it is peppered with links to all the relevant papers.

Bumetanide (BTN or BUM) is a FDA-approved potent loop diuretic (LD) that acts by antagonizing sodium-potassium-chloride (Na-K-Cl) cotransporters, NKCC1 (SLc12a2) and NKCC2. While NKCC1 is expressed both in the CNS and in systemic organs, NKCC2 is kidney-specific. The off-label use of BTN to modulate neuronal transmembrane Clgradients by blocking NKCC1 in the CNS has now been tested as an anti-seizure agent and as an intervention for neurological disorders in pre-clinical studies with varying results. BTN safety and efficacy for its off-label use has also been tested in several clinical trials for neonates, children, adolescents, and adults. It failed to meet efficacy criteria for hypoxic-ischemic encephalopathy (HIE) neonatal seizures. In contrast, positive outcomes in temporal lobe epilepsy (TLE), autism, and schizophrenia trials have been attributed to BTN in studies evaluating its off-label use. NKCC1 is an electroneutral neuronal Climporter and the dominance of NKCC1 function has been proposed as the common pathology for HIE seizures, TLE, autism, and schizophrenia. Therefore, the use of BTN to antagonize neuronal NKCC1 with the goal to lower internal Cl levels and promote GABAergic mediated hyperpolarization has been proposed. In this review, we summarize the data and results for pre-clinical and clinical studies that have tested off-label BTN interventions and report variable outcomes. We also compare the data underlying the developmental expression profile of NKCC1 and KCC2, highlight the limitations of BTN’s brain-availability and consider its actions on non-neuronal cells.

Btn Pro-Drugs and Analogs

To improve BTN accessibility to the brain, pro-drugs with lipophilic and uncharged esters, alcohol and amide analogs have been created. These pro-drugs convert to BTN after gaining access into the brain. There was a significantly higher concentration of ester prodrug, BUM5 (N,N – dimethylaminoethyl ester), in mouse brains compared to the parent BTN (10 mg/kg, IV of BTN and equimolar dose of 13 mg/kg, IV of BUM5) (Töllner et al., 2014). BUM5 stopped seizures in adult animal models where BTN failed to work (Töllner et al., 2014Erker et al., 2016). BUM5 was also less diuretic and showed better brain access when compared to the other prodrugs, BUM1 (ester prodrug), BUM7 (alcohol prodrug) and BUM10 (amide prodrug). BUM5 was reported to be more effective than BTN in altering seizure thresholds in epileptic animals post-SE and post-kindling (Töllner et al., 2014). Furthermore, BUM5 (13 mg/kg, IV) was more efficacious than BTN (10 mg/kg, IV) in promoting the anti-seizure effects of PB, in a maximal electroshock seizure model (Erker et al., 2016). Compared to BUM5 which was an efficacious adjunct to PB in the above mentioned study, BTN was not efficacious when administered as an adjunct (Erker et al., 2016). In addition to seizure thresholds, further studies need to be conducted to assess effects of BUM5 on seizure burdens, ictal events, duration and latencies.
Recently, a benzylamine derivative, bumepamine, has been investigated in pre-clinical models. Since benzylamine derivatives lack the carboxylic group of BTN, it results in lower diuretic activity (Nielsen and Feit, 1978). This prompted Brandt et al. (2018) to explore the proposed lower diuretic activity, higher lipophilicity and lower ionization rate of bumepamine at physiological pH. Since it is known that rodents metabolize BTN quicker than humans, the study used higher doses of 10 mg/kg of bumepamine similar to their previous BTN studies (Olsen, 1977Brandt et al., 2010Töllner et al., 2014). Bumepamine, while only being nominally metabolized to BTN, was more effective than BTN to support anticonvulsant effects of PB in rodent models of epilepsy. This GABAergic response, however, was not due to antagonistic actions on NKCC1; suggesting bumepamine may have an off-target effect, which remains unknown. However, the anticonvulsive effects of bumepamine, in spite of its lack of action on NKCC1, are to be noted. Additionally, in another study by the same group, it was shown that azosemide was 4-times more potent an inhibitor of NKCC1 than BTN, opening additional avenues for better BBB penetration and NKCC1-antagonizing compounds for potential neurological drug discovery (Hampel et al., 2018).

Conclusion


The beneficial effects of BTN reported in cases of autism, schizophrenia and TLE, given its poor-brain bioavailability are intriguing. The mechanisms underlying the effects of BTN, as a neuromodulator for developmental and neuropsychiatric disorders could be multifactorial due to prominent NKCC1 function at neuronal and non-neuronal sites within the CNS. Investigation of the possible off-target and systemic effects of BTN may help further this understanding with the advent of a new generation of brain-accessible BTN analogs.




Wednesday 21 December 2016

Synergistic Benefit of Low Dose Dopamine (Greek Coffee) and Diuretics (Bumetanide/Furosemide); better than Bromocriptine?


I did think of highlighting this post to the Bumetanide researchers in France, but I do not think they would take it seriously.


Another one to mention would be this new study, funded by Rodakis, to look at why some antibiotics improve some autism.  Dr Luna at Baylor College is running the study.  Its basic assumption is that the effect must be to do with bacteria, but as our reader Agnieszka has highlighted, common penicillin type antibiotics increase expression of the gene GLT-1 which then reduces glutamate in the brain.  It has nothing to do with bacteria.  Maybe for other antibiotics the effect does relate to bacteria.


But if you tell Dr Luna about GLT-1, quite likely she will not be interested.  




Researchers will compare the gut microbiome (bacteria, yeasts and fungi found in the gut) and metabolome (small biological molecules produced by the microbes) of those who experience a change in symptoms during antibiotic use to those who do not. The study may provide valuable insight into when and why these changes occur and how this information can be harnessed for future interventions.  


There is even a case study very well documented here:-


Beta-Lactam Antibiotics as A Possible Novel Therapy for Managing Epilepsy and Autism, A Case Report and Review of Literature

Petra, our regular reader from Greece, has pointed out that Bumetanide has a greater effect in her adult son, with Asperger’s, when taken with Greek coffee and suggested why this might be. 

Her reference is this article:- 





It shows that the diuretic effect of low dose furosemide, with dopamine, is greater than the effect of high dose furosemide.



The diuretic effect of Furosemide is via the transporter NKCC2, which is the same affected by Bumetanide. 

NKCC2 is found in your kidneys, while the very similar NKCC1 is found in your brain.  Furosemide and Bumetanide affect both NKCC1 and NKCC2.

The caffeine in coffee is known to indirectly produce dopamine in your body.

Greek coffee is nothing like your instant coffee or watery Starbucks coffee, it contains a serious amount of caffeine. 

The question is how does dopamine interact with furosemide/bumetanide and will the effect in the kidney (NKCC2) also affect the brain (NKCC1). 

By more effectively blocking NKCC1 in neurons you would further lower chloride levels and potentially further improve cognitive functioning.  

This would further validate Petra’s observation. 

Then we would consider if there is an alternative to Greek coffee, or just accept that caffeine is the simplest and safest method to enhance Bumetanide.    

In the then end my conclusion is that coffee, or just the caffeine, is a better option than a selective Dopamine D2 receptor agonist.  But there is an interesting drug called Bromocriptine that may be better in some cases. 

Not only is it a dopamine D2 receptor agonist, but Bromocriptine also “inhibits the release of glutamate, by reversing the GLT-1 (EAAT2) transporter”. 

We came across the GLT-1 (EAAT2) transporter when we found why some people with autism improve when on beta-lactam antibiotics (that include the penicillin ones).   

GLT-1/ EAAT2 is the principal transporter that clears the excitatory neurotransmitter glutamate from the extracellular space at synapses in the central nervous system. Glutamate clearance is necessary for proper synaptic activation and to prevent neuronal damage from excessive activation of glutamate receptors. EAAT2 is responsible for over 90% of glutamate reuptake within the brain 

We saw that the drug riluzole approved for the treatment of ALS (Amyotrophic Lateral Sclerosis) upregulates EAAT2/GLT-1.
I suggested that people with autism who improve on penicillin types antibiotics should get a similar effect from riluzole.  But riluzole is one of those monstrously expensive drugs.  

Based on my logic, we would then think that bromocriptine should help treat ALS (Amyotrophic Lateral Sclerosis).  What did I find when I looked it up:- 



So then how much does Bromocriptine cost?  It is a cheap generic.  So a cost effective potential drug for ALS. 

Bromocriptine has two potentially useful functions (Dopamine D2 and GLT-1),but it has numerous other effects:- 

Bromocriptine blocks the release of a hormone called prolactin, but this should not be an issue for males. 

Risperidone, one of only two drugs approved for side effects of autism, can boost levels of prolactin.  Elevated prolactin levels are linked to a range of side effects, including gynecomastia, or growth of breasts, in men and boys.  This did not stop the drug being approved.

Bromocriptine agonizes the following monoamine receptors

  • Dopamine D1 family
    • D1 (Ki=682 nM)
    • D5 (Ki=496 nM)
  • Dopamine D2 family
    • D2 (Ki=2.96 nM)
    • D3 (Ki=5.42 nM)
    • D4 (Ki=328 nM)
  • Serotonin 5-HT
  • Adrenergic α family
  • Adrenergic β family
    • β1 (Ki=589 nM)
    • β2 (Ki=741 nM)

  
This is why drugs have side effects. 

But for people with ALS who cannot afford riluzole, the cheap generic bromocriptine might be a good choice.

How about bromocriptine for autism? 

Well there was a trial in Italy a long time ago on girls with Rett syndrome 



Twelve typical cases of the Rett syndrome and one forme fruste were treated with bromocriptine for six months and then had a washout for two months followed by resumption of the bromocriptine treatment. During the first bromocriptine treatment there were improvements in communication and relaxation in some of the girls: a more regular sleep pattern was observed in 4 and a more varied facial expression in 8, and 4 girls began to utter a few words. The bouts of hyperpnea disappeared in 5 and grinding of the teeth in 3. There was also a reduction in stereotypic hand activities in 5 girls and signs of improved motor abilities in 3. The washout caused a general decrease in the positive effects of the previously administered bromocriptine and resumption of the treatment with this drug led to less marked improvement. Metoclopramide was tested in all the girls before the treatment, and it was noted that, while endorphins were hyporesponsive, prolactin was hyperresponsive. This test was repeated two months after the bromocriptine treatment had been performed and, while beta-lipotropin remained unchanged, beta-endorphin showed increased responsiveness.



Current use of Dopamine with Lower Dose Diuretics 

There is extensive knowledge of the effect of taking dopamine with a bumetanide type diuretic. 

Bumetanide by itself has a plateau above which a higher dose causes no further diuresis, but when combined with dopamine there is more diuresis.  Alternatively you can use a lower dose of bumetanide and get the same amount of diuresis by adding dopamine. 

Of interest to people with autism, it is found that you can reduce the amount of potassium lost for the same amount of diuresis.

    










The effects of a combination of dopamine and bumetanide were studied in eight patients with oliguria not responsive to conventional treatment. Dopamine was infused at a rate of 3 чg/kg/min and bumetanide was given as a 0.05-0.1 mg/kg bolus every 2 hours intravenously. Administration continued for 3 to 15 days. Urine output, blood urea nitrogen, serum creatinine, the ratio of urine to plasma osmolarity, free water clearance, and serum electrolytes were measured before, during, and after the administration period. Six of the eight patients responded with an increase in urine output and improvement of the other variables ; the other two did not. We conclude that the combination of dopamine and high-dose bumetanide is effective in increasing diuresis in critically ill patients in the early stages of oliguria



How does dopamine interact with NKCC1/2?

This is a very logical question, but there is something in the literature on this subject.  It does come from frogs, but it was all I could find.




The different murine D2-type dopamine receptors (D2L, D2S, D3L, D3S, and D4) were expressed in Xenopus laevis oocytes. The D2-type receptors were all similarly and efficiently expressed in Xenopus oocytes and were shown to bind the D2 antagonist [125I]sulpride. They were all shown to activate Cl influx upon agonist stimulation. Using the diagnostic inhibitor bumetanide, we were able to separate the Na+/K+/2Cl cotransporter component of the Cl influx from the total unidirectional Cl influx. The D3L subtype was found to operate exclusively through the bumetanide-insensitive Cl influx whereas the other D2-type receptors acted on the Na+/K+/2Cl cotransporter as well. The pertussis toxin sensitivity of the receptor-activated chloride influx via the Na+/K+/2Cl cotransporter varied between the various D2-type receptors showing that they may couple to different G proteins, and activate different second messenger systems.


In contrast to the D2 and D3 receptor subtypes, D4 receptor activity was not significantly altered by the presence of PTX, suggesting that in Xenopus oocytes it may couple with one or more PTX-insensitive G proteins to cause changes in Cl3 influx. By contrast, in the case of the D2 receptor, PTX reduced the total Cl3 influx mediated by the D2S isoform by approximately 67%, and that mediated by the D2L isoform by approximately 40% (Fig. 2A). However, the activities of the two components of this ion influx, namely the bumetanide sensitive Na/K/2Cl- cotransporter and the bumetanide-insensitive Cl- influx, differed between these two isoforms. While the bumetanide-insensitive Cl3 influx was reduced by approximately 60% by PTX for the D2L isoform, it was only slightly reduced for the D2S isoform (Fig. 2C). Thus, the majority of the inhibitory effect of PTX on the D2S-induced influx was caused by uncoupling from the signalling cascade that activates the Na/K/2Cl- cotransporter. On the other hand, the signal transduction pathway that activates the cotransporter after stimulation of the D2L receptor remained relatively unaffected by PTX (Fig. 2B), indicating that D2S and D2L couple to different G proteins when expressed in Xenopus oocytes. For the D3 receptor, both long and short isoforms showed a reduction (50^60%) in the presence of PTX, at the bumetanide-insensitive Cl- influx (Fig. 2C), whereas for both D3 receptor isoforms, PTX had little or no effect on the Na/K/2Cl- cotransporter, indicated by the bumetanide-sensitive component of the Cl3 influx (Fig. 2B).  

PTX = pertussis toxin
  

Caffeine among its many effects is effectively a dopamine D2/3 receptor agonist.





Conclusion

As I understand from the large scale trial use of bumetanide use in autism, there is indeed an issue with hypokalemia (loss of potassium).  

I would think that this should be solvable using a supplement and dietary potassium.  Agnieszka pointed out that kiwis have the advantage of potassium with little carbohydrate, as do avocados. Bananas and orange juice are the traditional potassium-rich foods for people on diuretics. 

This is a case where the care giver has to play an active role, it is not just about the doctor prescribing a pill.  The care giver has to manage the process to minimize the side effects.  So potassium needs to be managed, as does fluid intake. 

For people who struggle with hypokalemia, the idea of a lower dose of bumetanide, but with dopamine, could be interesting.  The other method is to add a potassium sparing diuretic like spironolactone. 

For my son, the dietary option, plus 250mg of potassium twice a day, is very effective.  Now I just have to persuade him to take a Greek coffee with his breakfast. 

For people whose autism responds to penicillin type antibiotics and who take bumetanide then Bromocriptine might be interesting as a caffeine alternative.