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Dr. Cameron
Dr. Cameron, Doctor
Category: Medical
Satisfied Customers: 12910
Experience:  American Board Certified in Emergency Medicine and Ivy League trained. Medical Review Officer trained in Drug Testing
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Please only answer if you know, thanks. XXXXX

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Please only answer if you know, thanks. XXXXX Block injects a medicine to block nerve signaling for about 4 hours. Is there any evidence or medical principle that supports the notion that after this 4 hours, the pain/sensitivity of the corresponding region (rectum) will come back to a level less than the original pain? That a series of these blocks, done a week apart, will produce a significant lasting reduction in pain by incrementally wiping out "nerve memory"? Or is pain relief limited to ONLY the few hours during which the medication is active?
Hi. My name isXXXXX and I am online and available to help you today. Thank you for your patience. I've not talked to you in a while.

I see that you still have over 50 questions that you received answers on, yet you did not give positive feedback. I hope you will not continue that trend with this thread....

To answer your question directly:

The pain relief is limited to the duration of time that the corresponding medication is active.

Is there anything else you would like to discuss at this point or have all your questions been answered to your satisfaction?

I hope this information was helpful for you. But I do work for tips so I want to make sure you are happy with me before rating me. If you have another question on this or a related issue feel free to fire away. You may also receive an email survey after our chat, if you don’t feel that I have earned a “10” rating in all areas, please let me know what I can do to meet your expectations.

Thanks in advance,

Dr. Rick MD FACS

Customer: replied 3 years ago.

You must be looking at the wrong account, because I give an excellent rating every time... in fact, JA has sent me two warnings that I'm giving out far too many excellent ratings.


Since you seem to be more worried about grubbing than actually addressing the user's question to earn that rating, I ask that you transfer this question to a different expert who actually wants to read and answer it. Thanks.


I'm not really worried about grubbing at all.....and we have talked before on issues such as this.

My day job as a surgeon pays the bills. I see JA as a service I can offer to those who can not afford or who can not access a physician directly.

I will opt out.

Have a good evening and best of luck to you.

Dr. Rick MD FACS
I would like to help you if I can
The pain pathways are really complex as you have probably figured out.
But there is no evidence that sequential blocks wipe out any sort of memory - in fact they tested this notion of giving one injection followed by another in other regions of the body:
The actual blocking of the pain is limited to the duration of the medication- which is why the pain returns.
That being said, a lot of pain is more than the activation of the peripheral nerves. It is also related to the interpretation of the pain by the brain, which can produce endorphins which make it feel good and combat the feeling of pain- I am sure that you heard of the runner's high or working through the pain, etc.
So, after getting the injection, although the medication has worn off, the relief of the pain as perceived by the brain can actually cause enough relaxation of the muscles (for example in spasm) so that there is less triggering in the future. An already irritated area will hurt more. If the area is allowed to recover, the pain is felt less in the future.

I hope that this helped.

Please leave positive feedback if it did :-)
Dr. Cameron, Doctor
Category: Medical
Satisfied Customers: 12910
Experience: American Board Certified in Emergency Medicine and Ivy League trained. Medical Review Officer trained in Drug Testing
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Customer: replied 3 years ago.

Great info, I'm glad I found someone with knowledge in this specific area. My rectum is severely inflamed the past couple years due to Crohn's, resulting in a persistent sore/bruised type pain, and intense pain spikes when I use the toilet (~20/day) due to spasms and the rectum trying to push it'self out. I had one block done, which reduced the pain, but for only 3-4 hours, then came back, along with the added soreness from the injection, so it really didn't seem worth it.

Are we saying that getting 3 more blocks will simply be a repeat of this first injection experience, and will not produce any long-term benefits?

Well, as mentioned before, it *might* help- because tissue that is in pain doesn't heal as well as tissue that is not- and inflammed tissue aggravates pain.
I imagine that you are working with a pain specialist.

Another option may be botox. - have you considered this?

I hope that this helped.

Please leave positive feedback if it did :-)

Customer: replied 3 years ago.

So to wrap up this question... The first article you referenced does not explore if there is any long-term or cumulative benefit to doing blocks (beyond the duration of the injected medicine). Have any studies shown whether or not benefits exist, and to what extent?


You stated "An already irritated area will hurt more."... so the blocks will increase my pain? I will ask my surgeon about that botox option.

I was not able to find any such studies over long term- this was divided by minutes. But I'll look again.And the blocks could help. It may allow the area to heal faster by decreasing pain-> better muscle relaxation-> less anal spams-> fewer fissure and Similar trauma
Customer: replied 3 years ago.

But if the medication only decreases pain for 3 hours out of a week, that's only 1% I'll be relaxing the muscles and thus free of the spasms... compared to 99% of the time I'll be having spasms. I don't see how a small moment of relaxation can be considered a patient's path of healing, when it's engulfed in a sea of spasms. Or am I missing something?

it actually can, by decreasing lactic acid build up etc.
And it can help psychologically which is huge