Posted by ed_uk on December 12, 2004, at 15:11:30
In reply to Re: To Tom » ed_uk, posted by TomG on December 12, 2004, at 11:42:49
Hi everyone,
One of the reasons that classical neuroleptics are frequently so poorly tolerated by patients is that they are sometimes prescribed such vast doses. 'Overdosing' patients on haloperidol (Haldol) has been particularly common, especially before the atypical antipsychotics were available. The British National Formulary used to state that doses of up to 200mg/day of haloperidol could be used for the treatment of schizophrenia. The maximum dose has now been reduced to 30mg/day but this is still far in excess of the optimum dose for most patients. Consider that some people with schizophrenia only need 0.5mg a day!! Trials comparing atypical APs to Haldol have sometimes used large Haldol doses of up to 20mg/day!! Such trials have usually been concluded by triumphantly announcing the superior tolerability of the new drug. Trials such as these inevitably overexaggerate the advantages of atypicals- mmm I wonder WHY such high doses of Haldol are used? Maybe the pharm companies are afraid that if low doses of Haldol were used the side effect profile of their new and highly expensive drug might not prove to be superior at all!!!
Very low doses of haloperidol seem to be just as effective as high doses for the majority of patients. Only a small minority of people will gain additional benefit from high doses but the side effects of high dose are commonly intolerable. Adverse effects such as akathisia are very much dose-dependent.
2mg/day of haloperidol can be an effective treatment for schizophrenia.......
This double-blinded, randomized controlled study compared the efficacy and tolerability of 2 vs. 8 mg/d of haloperidol over 6 wk in 40 subjects with first-episode psychosis. Both treatments were equally effective in reducing the PANSS Total and subscale scores. The low dose of haloperidol was better tolerated, with fewer extrapyramidal side-effects, less frequent use of anticholinergic medication and smaller elevations in prolactin levels. Using a low dose of haloperidol is at least as effective as, and better tolerated than a high dose of haloperidol in the treatment of first-episode psychosis.
Sometimes, doses of haloperidol <1mg/day are best....Determining the optimal dose of haloperidol in first-episode psychosis.
This study set out to determine whether ultra-low doses of haloperidol could successfully treat patients with first-episode psychosis. Thirty-five patients with a first episode of psychosis were treated with haloperidol in an open label, fixed protocol over a 12-week period with doses restricted to 1 mg per day for the first 4 weeks. Twenty-nine (83%) remained on haloperidol after 12 weeks at a mean dose of 1.78 mg per day, 16 (55%) had stabilized on 1 mg/day or less. The mean percentage reduction in Positive and Negative Symptom Scale score between baseline and 6 and 12 weeks was 30.3% (SD 20.9%) and 41.4% (SD 16.6%), respectively. There were *no* significant differences in mean extrapyramidal symptom ratings between baseline and 12 weeks. Ultra-low doses of haloperidol are effective and well tolerated in first-episode psychosis. Initial doses should be maintained for a sufficient period of time to allow for the medication to take full effect.
To summarise.... many of the alleged advantages of atypicals may in fact be an artifact of the trials which have compared their safety and efficacy to vastly excessive doses of classical neuroleptics.
The tendency of doctors to prescribe mega-doses of haloperidol is mirrored by the haloperidol (Haldol/Serenace) products available on the UK market........
20mg Serence tablets ahhhh!
Single Serenace ampoules of 20mg.
Unfortunately, Haldol is not the only classical AP that people have received excessive doses of.... fluphenazine, trifluoperazine and other potent D2 antagonists have also been used to excess.
My message is.....Although the discovery of the atypical APs has been a great advance, the superior tolerability of the newer drugs has been overstated. Although the atypicals have been a miracle for some people, others might be substantially better off on low doses of older drugs.
Even the dreaded haloperidol has advantages....
Small weight gain compared to most atypicals. Occasionally causes weight loss!
Few autonomic side effects eg. low risk of hypotension.
*Low* doses often produce little sedation.
Risk of extrapyramidal side effects depends on dose, low doses are substantially more tolerable.
Risk of TD is reduced by using low doses.
It is very cheap.
It has been available for a long time and has been studied in a large number of clinical trials.
My own experience with classical APs (Thorazine for anxiety) was that low doses were relatively easy to tolerate. High doses caused such severe side effects that I would not wish such torture on my worst enemy.It scares me to think that some patients who become agitated due to APs may have their dose increased by doctors who are unaware of the fact that APs can induce severe agitation and even panic in some individuals.
To Tom..... some people find low doses of trifluoperaine (Stelazine) activating. As ever, high doses are likely to make you feel (and look) dreadful.
Regards,
Ed.
poster:ed_uk
thread:427750
URL: http://www.dr-bob.org/babble/20041211/msgs/428369.html