Posted by Sunnely on October 17, 2000, at 19:01:18
In reply to Doc Gave Me an Antipsychotic - Am I crazy?, posted by GLYN on October 16, 2000, at 19:33:12
Hi Glyn,
I can't comment as to what exactly is your diagnosis. But if your diagnosis is only an anxiety disorder and not schizophrenia, then Mellaril is absolutely containdicated. (At least here in the U.S. I noticed that you're from the UK.)
As of July 7, 2000, Novartis, the maker of Mellaril (thioridazine HCl) sent every MD/Pharmacist a Dear Doctor/Pharmacist letter informing them of major modifications to the labeling of this medication. In summary, the following are the labeling modifications:
1. A boxed WARNING has been added to prominently advise clinicians that Mellaril (thioridazine HCl) has been shown to prolong the QTc interval (an electrocardiogram abnormality) in a dose related manner, and drugs with this potential, including Mellaril, have been associated with torsade de pointes-type arrhythmias and sudden death. (This condition is similar to the sudden heart deaths due to the use of Seldane, Hismanal, and Propulsid, now all off the US market. Pimozide, an antipsychotic which remains available in the US market, also has the potential to cause this serious problem and sudden deaths have been reported.)
2. Mellaril is now indicated ONLY for schizophrenic patients who fail to show an acceptable response to adequate courses of treatment with other antipsychotic drugs, either because of insufficient effectiveness or the inability to achieve an effective dose due to intolerable adverse effects.
3. Mellaril is now contraindicated with certain other drugs, including fluvoxamine (Luvox), propranolol (Inderal), pindolol (Visken), any drug that inhibits the cytochrome P450 2D6 isoenzyme, e.g., fluoxetine (Prozac) and paroxetine (Paxil), and agents known to prolong the QTc interval; Mellaril is also contraindicated in patients known to have reduced levels of the cytochrome P450 2D6 isoenzyme as well as in patients with congenital long QT syndrome or a history of cardiac arrhythmias.
4. Patients being considered for treatment with Mellaril should have a baseline ECG performed and serum potassium levels measured. Serum potassium should be normalized before starting treatment and patients with a QTc interval greater than 450 msec (milliseconds) should not receive Mellaril. Periodic ECG's and serum potassium levels during Mellaril treatment may be useful and Mellaril should be discontinued in patients who are found to have a QTc interval over 500 msec.
5. Treatment of Mellaril overdosage should entail immediate cardiovascular monitoring, to include continuous electrocardiogram monitoring to detect arrhythmias. Drugs that may produce additive QT-prolonging effects, such as disopyramide (Norpace), procainamide (Pronestyl), and quinidine (Cardioquin, Quinaglute), should be avoided in the treatment of Mellaril overdosage.
As a side note, blame Pfizer, the maker of Zeldox (ziprasidone), for the above-mentioned Mellaril labeling modifications.
poster:Sunnely
thread:46508
URL: http://www.dr-bob.org/babble/20001012/msgs/46602.html