Suggest Treatment For Pure Autonomic Failure

Posted on Tue, 1 Jul 2014

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Tue, 1 Jul 2014 Answered on

Wed, 23 Jul 2014 Last reviewed on

Question : I have PAF Pure Autonomic failure ( hyper-hypo tension) orthostatic hypotension). I have been prescribed both losartan potassium and nefedipine ER by different specialists but not autonomic specialists. Do you know which one is better to take given my condition. I need to lower my BP when lying and sitting, but not lower it too much when standing. I have lower levels of norepinephrine due to loss of sympathetic nerve activity. Because my condition is considered rare there is not much information on how to lower blood pressure only how to raise it. Right now however it is on the high side so I need to find how how to lower it when I am lying and sitting but not lower it too much when standing. I have tried short acting nefedipine but it is too erratic. XXXXXXX

Answered by Dr. Benard Shehu (2 hours later)

Brief Answer:
Following answers to your queries...

Detailed Answer:
Hi there,

I have gone through your medical history carefully and feel sorry for the situation you are in.

PAF is one of the cardio-vascular problems, which is handled by cardiologist. If cardiologist, after evaluations would judge he/she can manage your situation, then, no need for angiologist opinion. Otherwise, angiologist should be consulted too.

Autonomic failure does not need a specific specialist. Autonomic means that sympathetic functions are damaged. In your case, the damage is caused due to loss or sympathetic nerve activity (autonomic neuropathy).

Now, the most important thing is to lower your blood pressure and avoid severe drops when standing up.

- the most important thing is to avoid factors that can trigger such episodes:

- Discuss with your cardiologist to avoid taking your anti-hypertensive drugs during the day; and to limit their intake only at night

- do not take fluids at bedtime; try to have them throughout the day

- should raise your head when lying down

- if nifedipine is too erratic, then, I suggest to use: clonidine at the evening; nitrates transdermal during the night and taken off in the morning (not during the day)

You can have more information at the following link:
http://hyper.ahajournals.org/content/45/4/469/T4.expansion.html

Hope it was of help! Let me know if you have further queries!
Dr.Benard

Above answer was peer-reviewed by : Dr. Raju A.T

Follow up: Dr. Benard Shehu (28 minutes later)

I am very familiar with all the above suggestions and have use nitro patch at night and have seen the best autonomic doctors in country. However my blood pressure now gets quite high during the day sitting and occasionally standing. that is why I am trying to take a long acting BP medication. The Cardiologist I consult says take Losartan, the one autonomic doctor locally says the nefedipine ER. The autonomic doctors I have discussed this with for the most part are not very knowledgeable about the detail effects of these 2 drugs as they are used to very severe cases (i.e. people can't even stand up at all). The cardiologist I see is not very knowledgeable about the autonomic Dysfunction. I need an opinion from a Cardiologist who is very experienced with these 2 drugs and how they affect the autonomic system or which one would be the best choice given my condition. I have an extensive drop in BP standing up but has never been so low that I have fainted but right now off drugs my standing BP is normal systolic 110-130 but sitting and lying down close to 200 or over. the nitro patch has worked at night to lower BP to 150-180 but during the day I need something to lower BP.

Answered by Dr. Benard Shehu (6 hours later)

Brief Answer:
Continue taking Losartan to see results...

Detailed Answer:
Hi back,

I understand your worries.

The vaso-dilatator effect of Nifedipine ER might aggravate hypotension when standing up. Instead, the use of Losartan has been shown beneficial in many studies due to its effect on sympathethetic and renin-angiotensin-aldosteron systems.

So, taking Losartan during the day will help you lower your high BP without causing severe vaso-dilatation as in case of nifedipine.

Other lifestyle and diet changes should be considered too.

Dr.Benard

Above answer was peer-reviewed by : Dr. Raju A.T

Follow up: Dr. Benard Shehu (6 hours later)

That information is very helpful. Could you describe in a little more detail how Losartan acts on the sympathetic nervous system.

Answered by Dr. Benard Shehu (37 hours later)

Brief Answer:
Changes in plasma renin activity...

Detailed Answer:
Hi back,

Happy to know I have been of help.

With regards to mechanisms of lowering supine hypertension in PAF patients by Losartan, I can say that this is achieved through blocking the renin-angiotensine system and related changes. The end-result will be decreased blood pressure with improved cardiac output, and improvement in systemic vascular resistance.

Hope it answered to your queries!
Dr.Benard

Above answer was peer-reviewed by : Dr. Vinay Bhardwaj