Jump to content

How Midodrine (proamatine) Helps


robster
 Share

Recommended Posts

Hi all,

This is my first post, having only recently discovered dinet.

I have the POTS variety of chronic orthostatic intolerance. In terms of measurable phenomena, my heart rate goes from about 70 beats/min lying down to 85 while sitting and around 115 when standing up. My blood pressure slowly climbs up while I'm standing. I'm not usually aware of this (only if I take my pulse) but, as would be familiar to many of you here, I am painfully aware of how weak, lightheaded, uncoordinated, brain fogged, nauseous and exhausted I am.

I have been getting good results with judicious use of Midodrine. Within about 30 mins of taking a dose, my functional ability increases markedly and I'm able to do many things physically and mentally that would otherwise be beyond me. After a few hours the curtain comes down, presumably as the drug finishes metabolising or whatever, and the exhaustion, brain fog etc etc once again take over. I am quite sensitive to some of this drug's dose-related side effects so I need to be careful to under-dose to be safe. It has been a real miracle drug for me, allowing me to once again be somewhat in control of my own energy (On really bad days, however, my usual dose won't work).

The confounding thing is that this drug doesn't seem to change my tachycardia at all, even though it wipes away many of my functional limitations for hours at a time. It does elevate my blood pressure, but my blood pressure before the drug was never low, always normal for my age (or slightly high).

This leaves me wondering why the drug works for me at all.

I'd love to hear from other people who take midodrine/proamatine for POTS, especially to hear about whether the drug makes you feel better and if that improvement bears any relation to what your heart rate and bp are doing.

Thanks,

Rob

Link to comment
Share on other sites

Hi Rob, welcome to the forum!

I took low dose midodrine for several months (only 2.5mg). Personally I didn't find that it helped at all but I suspect that my dose was too low. Midodrine is supposed to help by elevating BP and getting more blood to the brain so helping with the concentration type problems. Some people with POTS actually constrict the blood vessels in the brain when upright so reducing the blood flow to the brain (J Stewart has done research with transcranial doppler showing this). I wonder if in your case the midodrine raises BP enough to either prevent that sort of constriction or overcome it and improve blood flow to the brain? So long as your BP is not getting dangerously high (keep a record of your BP and show it to your doctor) and you are getting a benefit from the midodrine then I wouldn't worry too much about exactly how it works. There is so much about POTS that is unknown!!.

Flop

Link to comment
Share on other sites

Thanks Flop,

My dose is relatively low, about 7.5mg spread through the day. As you say, I do have to keep an eye on my blood pressure, as it is creeping up now that I'm on this drug. Using some of my drug-delivered relief to build up my muscles should help with that.

Cheers,

Rob

Link to comment
Share on other sites

It seems to help me out sometimes...on really bad mornings it can be very beneficial. It is supposed to raise your blood pressure, but I've heard it can also help 'constrict' your blood vessels (I think) and that's what probably helps me.

My EP said not to worry as long as my BP stayed under 140/95 which it has. I usually try to take my BP an hour or so after Midodrine in the AM before work and it ranges from 115/75 to 135/95 on average. And if it's the higher end and I sit for 2 minutes it usually falls 5-10 points. And this is on 10mg in the AM after the hour or so it really takes to kick in.

Then I take 5mg at lunch and if really feeling down 5mg at night.

Link to comment
Share on other sites

I'm on 15 mg spread throughout the day. I too have to keep an eye on my BP. Rob, you should ask about a bata blocker to help with the heart rate. I'm on one to lower and control my heart rate. It will also lower your BP, so that's why so much midodrine for me. It seems to regulate me most days. I still am working on dosage, so not quite where I want to be, but getting there.

Link to comment
Share on other sites

I take midodrine around the clock (not typical) every 4 hours. during the day I take 6.25 mgs, at night 5mgs. It does help, I just hate that it's so short-acting. I take it with florinef, which currently is a good combo. My bp is typically 115/75, even on all those bp uppers. I started on just the midodrine, but had a crash this summer when it wasn't enough. and when we upped the dose, my hr would slow too much-- so had to add the florinef.

Link to comment
Share on other sites

New Computer, so if this appears twice, in part, my apologies.....

Anyway, my Dr just put me on this Midodrine, and I'm afraid to start taking it.....my bp has been trending upward in the past few months...usually it's about normal, or above, never low, so I'm afraid this med will put me over the top....so many weird symptoms anyway, and afraid of side effects also. Any extra info & support I would appreciate.

Thanks,

Tommy

Link to comment
Share on other sites

midodrine (from drugs.com):

"Midodrine - Clinical Pharmacology

Mechanism of Action

Midodrine hydrochloride forms an active metabolite, desglyMidodrine, that is an alpha1-agonist, and exerts its actions via activation of the alpha-adrenergic receptors of the arteriolar and venous vasculature, producing an increase in vascular tone and elevation of blood pressure. DesglyMidodrine does not stimulate cardiac beta-adrenergic receptors. DesglyMidodrine diffuses poorly across the blood-brain barrier, and is therefore not associated with effects on the central nervous system.

Administration of Midodrine hydrochloride results in a rise in standing, sitting, and supine systolic and diastolic blood pressure in patients with orthostatic hypotension of various etiologies. Standing systolic blood pressure is elevated by approximately 15 to 30 mmHg at 1 hour after a 10-mg dose of Midodrine, with some effect persisting for 2 to 3 hours. Midodrine hydrochloride has no clinically significant effect on standing or supine pulse rates in patients with autonomic failure."

I was dxed with the Hyperadrenergic flavor of POTS in November and midodrine was not a Rx that was suggested for me, apparently I squeeze hard enough that many nurses and doctors cannot find a pulse in my wrists when I stand. :blink: (Actually it's kinda fun to watch them desperately search for a pulse when they know I'm not dead since I'm still standing there!) As an example, my standing BP this morning was 135/111 (yes, it hurts!)

Welcome to the forum!

Link to comment
Share on other sites

  • 2 weeks later...

Thanks Firewatcher......

I am working so slowly towards what my dosage is supposed to be- took 5mg for first time this morning, and my head is "crawling"- it does seem to help me get going in the a.m., but has anyone else had experience with this side effect? if it is a side effect? My body comes up with so many strange things to do these days, but the doc did say it may make my scalp itch--is this what he meant?

Oh- Firewatcher- "Florrid POTS here.

Link to comment
Share on other sites

In theory midodrine would be helpful in all forms of POTS - or all theories of what causes POTS:

Peripheral neuropathy - if there is an autoimmune process causing your pots, you are more likely to experience blood pooling in the legs, and midodrine is a peripheral vasoconstrictor - constricting your legs so that their is more blood available to your thorax and heart, and probably more importantly, your brain on standing.

Under this theory, the sympathetic overactivity that results in tachycardia and tremors would likely subside under this model when their is adequate blood flow to the heart and brain although some researchers who prescribe to this view think that the denervation causes overactivity of the remaining nerves = sympathetic overactivity not mediated by symptoms.

NET deficiency - some researchers believe many POTS patients have impaired reuptake of Norepinephrine. This causes excessive vasonconstriction on standing, reducing blood flow to the brain and heart (although it is hard to explain how this would cause reduced thorax blood availability and blood pooling). Midodrine causes peripheral vasoconstriction, pushing blood to the brain. This would not change the excess sympathetic symptoms that in this scenario would be caused by excessive levels of norepinephrine - even when you are no longer dizzy.

Nitric Oxide bioavailability - under this model, excess angiotensin II in some POTS patients is causing a nitric oxide deficit in arteries, again leading to vasoconstriction - same as above, but they suspect that Angiotensin II has a potent effect on the sympathetic nervous system, so again tachycardia perhaos with symptoms.

Normal Flow POTS - this model is characterised by pooling almost exclusively in the stomach and excessive peripheral vasonconstriction. Midodrine being a vasoconstrictor would probably NOT be helpful.

Link to comment
Share on other sites

Help me understand this better because I have been staring at my midodrine prescription for 3 weeks and have yet to take one....

How do we know what form of pots we have? I have definte blood pooling in the abdoment and my legs are mottled from vasocontriction so does that mean I am a normal flow? And midodrine wouldn't help me?

Link to comment
Share on other sites

Your doctor would be a good person to speak to, but if a patient had blood pooling in the stomach and excessive vasoconstriction of your hands and feet/arms and legs it might be less helpful than the positive responses that people with excessive blood pooling experience.

It may however decrease the NE response to standing so may still help.

There is a medication that starts with O that has been tested on POTS patients that seems better suited to reducing blood pooling in the stomach.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...