Dosing of Wellbutrin SR versus Wellbutrin XL

[JohnBoy2000]

I know the typical protocol, but, realistically, is it possible to dose the SR version twice in the morning, as oppose to splitting the dose?

Also, with XL, assuming it works 24 hours, wouldn't that induce a greater possibility for insomnia than the SR which, should be worn off by bed time?

I'm just familiarizing myself now with the drug.
A lot of anecdotal reports suggest there is a greater efficacy with the SR version, oddly, than the XL, but clinical trials do not allude to this in any capacity what so ever.

Also - it's outlined that steady state blood plasma levels are not reached until two weeks after commencement but, it's also said that it is one of the more quick acting AD's so, in terms of reaching a steady efficacy, what time period would one be looking at?
Would we be seeing maybe, 70% efficacy after say, a week?


I understand it's the most commonly used noradrenergic, excluding any effect on serotonin, which most definitely seems to be a unique property with AD's.
There are some tricyclics that focus on noradrenaline, but also implicate the muscarinic acetylcholine receptor, and do have an effect on serotonin to some degree also.

Then we have Reboxotine, but, apparently, does worse than placebo by a significant margin in clinical trials so, don't know what's going on there.

Desipramine seemed like the most appealing noradrenergic option but, it's not available in Europe, period.
I don't know what's up with yankee land, whether it's common there or not...

 

[Dresden]

They both suck.

 

[JohnBoy2000]

Any one??

 

[JohnBoy2000]

One clinical trial tells me that bupropion can be dosed up to 750mg in inpatients...

 

[AlphaMethylPhenyl]

In very rare cases, that may be so

 

[Coolwhip]

AFAIK there hasn't been a lot of evidence that doses above 150mg are anymore efficacious, but can result in higher seizure risk and raise the rate of other side effects. There has been some controversy over the FDA ever approving 300mg versions in the first place, just allowed drug reps to convince doctors to continue prescribing higher doses when the 150mg versions were found ineffective. It's also suspected that most of the relief provided by bupropion is not from the parent compound but instead from long-acting active metabolites.

 

[JohnBoy2000]

AFAIK there hasn't been a lot of evidence that doses above 150mg are anymore efficacious, but can result in higher seizure risk and raise the rate of other side effects. There has been some controversy over the FDA ever approving 300mg versions in the first place, just allowed drug reps to convince doctors to continue prescribing higher doses when the 150mg versions were found ineffective. It's also suspected that most of the relief provided by bupropion is not from the parent compound but instead from long-acting active metabolites.

Have you got links or clinical trial data that outlines this in any way?

I'm not necessarily questioning it just, certainly interested to read more about it, especially the efficacy stemming from the metabolites, which would suggest that SR/XL wouldn't really matter so much, provided there's not one big great dump of bupropion into the system all at one time.... no?

 

[Coolwhip]

http://www.ncbi.nlm.nih.gov/pubmed/9663366

There's one, don't have time right now to find more. You could also consider nortriptyline if looking for a noradrenergic anti-depressant, and I'm not sure how much actually ends up in your system but IIRC desipramine is a metabolite of imipramine, although if you are trying to avoid SERT affinity it doesn't do you any good.

 

[JohnBoy2000]

http://www.ncbi.nlm.nih.gov/pubmed/9663366

Clin Ther. 1998 May-Jun;20(3):505-16.
A multicenter evaluation of the efficacy and safety of 150 and 300 mg/d sustained-release bupropion tablets versus placebo in depressed outpatients.

Reimherr FW1, Cunningham LA, Batey SR, Johnston JA, Ascher JA.
Author information

• 1University of Utah Medical Center, Salt Lake City, USA.

Abstract

This multicenter, randomized, double-masked, placebo-controlled, parallel-group study compared the antidepressant efficacy and safety of bupropion sustained-release (SR) tablets (150 mg QD or 150 mg BID) with placebo in outpatients with moderate-to-severe depression. The study consisted of a 1-week placebo phase followed by 8 weeks of active treatment with bupropion SR 150 mg/d (150 mg QD, n = 121) or 300 mg/d (150 mg BID, n = 120) or placebo (n = 121). Efficacy was measured by changes in scores on the 17-item Hamilton Rating Scale for Depression(HAM-D) and the Clinical Global Impressions for Severity of Illness (CGI-S) and Clinical Global Impressions for Improvement of Illness (CGI-I) scales. Safety was monitored by regular assessment of vital signs and adverse events as well as by pretreatment and posttreatment physical and clinical laboratory examinations. By day 56, both bupropion SR treatments were more effective in relieving the symptoms of depression than was placebo. Compared with those receiving placebo, patients in the bupropion SR 150- and 300-mg/d groups had significantly reduced symptoms by treatment day 56, as measured on the 17-item HAM-D, CGI-S, and CGI-I scales (P < 0.05). Bupropion SR was well tolerated, with no serious adverse events reported by bupropion-treated patients; 95% of all reported adverse events were of mild or moderate intensity. No clinically significant changes in vital signs, laboratory test results, or physical findings were observed. A greater mean weight loss was observed at the end of treatment in both the bupropion SR 150-mg (0.5 kg) and bupropion SR 300-mg (1.0 kg) group compared with placebo (0.2 kg). We found that bupropion SR 150 mg administered either once or twice daily was more effective than placebo in treating depression and that once-daily dosing appears to be at least as effective as twice-daily dosing. Should this prove true, depressed patients may be able to benefit from the convenience and improved tolerability associated with once-daily dosing.


I'll be damned!!

Cheers for the link.

If you have any others to hand, let 'em fly.