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Date of last update: 10/20/2017.

Forum Name: Hypertension

Question: How Propranolol in Time release (TR) form works?

 Amjad_Ranga - Mon Jan 05, 2009 11:47 pm

Respected Doctor.
I'm taking propranolol for dealing with panic situations on PRN basis.
In India we get propranolol in two forms: One in normal tablets form and other in capsules with some TR tag i.e; Time released mode.

I would like to know How TR capsules work? and for as and on need basis (PRN) which option is better to take propranolol in normal tablets form or in TR capsules form?
Your response is higly sought after.
Thanks in Advance.
 John Kenyon, CNA - Tue Jan 06, 2009 9:32 pm

User avatar Hello -

If by asking how propranolol TR works, I'm assuming you mean how the Time Release function is designed, but in case you are wondering about the function of propranalol and beta blockers in general, I will explain both. starting with the TR function first (as opposed to immediate release version): Time release propranolol is simply a capsule containing propranolol hydrochloride, soluble in water, but formulated from a number of different batches, each made using different inactive ingredients which slow the dissolving and absorption of various parts of it over time, at varying rates, so that it's not all absorbed at once; some remains unchanged in the GI tract, liver or bloodstream for longer periods of time, while other portions of the medication is absorbed at once. There are a large number of variants, specifically formulated for each capsule uniformly, so that each capsule behaves almost identically to all the others in terms of release of medication into the bloodstream.

Regular propranolol is all unaltered in this way, not bound to anything which will slow the absorption to take place naturally. It's important to understand that there is no simple milligram-for-milligram relationship between the two forms, since much of the time-released form is bound to other inactive ingredients, so, for instance, 20 mg. of regular propranolol taken four times daily should be replaced by 80 - 120 mg. of the time-released form taken usually taken once daily.

Now then: the way propranolol and other beta blockers work, in general, is to block the beta adrenergic uptake receptors in the body, which is how naturally-produced adrenaline reaches its destination and manages to cause the "rush", increase in muscle tone, and all other bodily functions affected by adrenal release. Beta blockers block the uptake of adrenaline at the receptor sites rather than reducing the output of adrenaline. Propranolol is a non-cardiac-seclective form, and is the oldest of all the beta blockers. By blocking uptake of adrenaline at all sites in the body, it reduces the effects of adrenaline, whether on a chronic basis or in anticipation of panic situations such as you will be using it for.

Since you will be using propranolol as a means of aborting or controlling emotionally stressful situations which could trigger panic, if these are situations that can be anticipated or if it is intended to abort or at least ease the effects of panic attacks, then the regular (not time-relaease) version is going to be more effective, and is in general better for use on an as-needed rather than therapeutic basis. It takes effect a lot more quickly than the time-released version, for obvious reasons, and it also clears the system more quickly when it is no longer needed.

I hope this answers your concerns. Good luck to you with this. Please follow up with us as needed.

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