Posted by Sunnely on March 20, 2001, at 20:11:08
In reply to Re: I'm scared to try Geodon..., posted by Anna P. on March 20, 2001, at 12:38:02
Prolonged QTc is the time it takes for the electrical system of the heart to repolarize. It is measured in msec (milliseconds). Between 350-440 msec is normal; between 450-500 msec is a potential concern; longer than 500 msec poses increased risk of arrhythmias (heart beat irregularities). Prolonged QTc can be a harbinger to a more serious heart beat irregularity called "torsades."
If you do not belong in the following groups of people, your fear of using Geodon is most likely unwarranted:
1. People with congenital long QT syndrome. Some people are born with this heart condition. Geodon is contraindicated in people with this condition. If you have had episodes of palpitations and syncope (passing out), you need to have a heart work up (evaluation) to rule out this possibility.
2. People who take drugs known to prolong QTc. Example of these drugs are (not a complete list) terfenadine (Seldane), astemizole (Hismanal), cisapride (Propulsid), pimozide (Orap), thioridazine (Mellaril), quinidine (Quinaglute), sotalol (Betapace), sparfloxacin (Zagam). The first 3 drugs above are no longer available in the US market. Your doctor and/or pharmacist should ask you if you are taking other drugs (especially those with potential to prolong QTc) before prescribing you Geodon. If they don't ask you, make sure you volunteer this information.
3. People with recent heart attack, those with uncompensated heart failure, and those with known history of heart arrhythmias should not take Geodon.
4. People with hypokalemia (low potassium level). If you are taking a diuretic (water pill), your potassium level should be regularly checked and if low, potassium supplement should be given. Low potassium makes the heart more irritable and prone to heart beat irregularity including prolonged QTc and possible serious heart beat irregularity. People with active eating disorders (anorexia and bulimia) may also be at risk for low potassium level. (Abuse of laxatives not uncommon with these people.) For these people, electrolytes (includes potassium) should be checked before starting Geodon.
5. People with hypomagnesemia (low magnesium level). Seen more especially with the active alcoholics. Electrolytes including potassium and magnesium should be checked first before starting Geodon on these people.
6. People who recently overdosed on tricyclic antidepressants. Electrocardiogram should be monitored and make certain they are free of prolongation of QTc before starting Geodon. Better yet, if antipsychotic drug is needed, try a different one.
To go back in time, ziprasidone (originally named Zeldox), was submitted for FDA approval in March 1997. However, Pfizer, the manufacturer, received notification from the US FDA in the summer of 1998 indicating that approval of ziprasidone would be delayed. The primary reason for this non-approval was apparently safety concerns related to potential heart side effects, specifically prolongation of the QTc interval, which has become a controversial issue for new antipsychotics. Pfizer collected more data and did more studies regarding its safety. Pfizer conducted further clinical trials pitting ziprasidone against haloperidol (Haldol), olanzapine (Zyprexa), risperidone (Risperdal), and quetiapine (Seroquel). The heart effects of each of the drugs were measured and monitored at optimum doses. Each drug was then compared with thioridazine (Mellaril), the older antipsychotic known to exhibit the strongest effect on QTc interval and now designated by FDA as a second-line drug due to its strong potential for heart arrhythmias.
The study revealed that the prolonging effect on QTc interval for ziprasidone was indeed longer than the four comparison atypical antipsychotics, but was much shorter than that seen with thioridazine. As a result, the approved labeling for ziprasidone includes extensive language warning of the theoretical potential for the drug to cause heart arrhythmias.
After nearly 4 years, Pfizer was able to convince the FDA that ziprasidone offered sufficient enough benefits for patients with schizophrenia to outweigh its potential for serious side effects. (Note: The FDA declined to approve Pfizer's original trade name, Zeldox, because of, it said, "similarities in spelling or pronunciation which may cause confusion with the proprietary name or the established name of a different drug or ingredient." The FDA was concerned about similarities between Zeldox and two other medications, Zyvox, Pharmacia & Upjohn's latest high-powered antibiotic, and Zoladex, a chemotherapeutic drug for prostate cancer made by AztraZeneca. The FDA approved Pfizer's request to use the trade name Geodon, pronounced gee-oh-don, instead of Zeldox.)
On the bright side, one big advantage of ziprasidone over the other atypical antipsychotics is its less propensity to cause weight gain. In fact, the drug appears to be "weight neutral." This is significantly different from its fellow antipsychotics' tendency to induce often significant gains in a patient's weight. Weight gain has long been considered a barrier to patient compliance with antipsychotic medications.
Another potential advantage of ziprasidone over its antipsychotic counterparts is its less propensity to cause elevations of cholesterol. Total cholesterol, LDL cholesterol (bad cholesterol), HDL cholesterol (good cholesterol), and triglyceride levels are important predictors of cardiovascular disease risk. In contrast to the other atypical antipsychotics and Mellaril, in a clinical trial, the ziprasidone group demonstrated marked median decreases from baseline in total cholesterol and LDL cholesterol, with no impact on HDL cholesterol. In recent clinical studies, it was consistently demonstrated that weight gain is associated with increased in blood sugar (diabetes) and triglyceride levels. Among the atypical antipsychotics, Clozaril and Zyprexa are more commonly linked to significant weight gain, diabetes, and elevations of triglycerides.
Although we need more time to determine its real risk, Geodon, just like the other atypical antipsychotics, probably has low risk for tardive dyskinesia (TD). Of course, some people are more prone to develop TD than others. The highest risk are the elderly people and those with concurrent neurological conditions or brain diseases. Again, time will tell.
+++++++++++++++++++++++++++++++++++++++> > I don't respond any more to drugs. Geodon was my hope. I have it already, but I'm scared to try it. I've read the medical insert that lists not only the increase in QTc interval, heart beat increase, tardive diskinesia and sudden death.
>
> Anna P.
poster:Sunnely
thread:56412
URL: http://www.dr-bob.org/babble/20010319/msgs/57019.html