Side Effects of Geodon (ziprasidone)

Geodon (ziprasidone) is an oral and injectable anti-psychotic drug used to treat psychoses such as schizophrenia and the manic symptoms of bipolar disorder (manic depression).

Although the mechanism of action of Geodon is unknown, like other anti-psychotics, it inhibits communication between nerves of the brain. It does this by blocking receptors on the nerves for several neurotransmitters, including dopamine and serotonin. It also inhibits the re-uptake of serotonin and norepinephrine by nerves in the brain like some anti-depressant drugs.

Geodon is associated with little or no weight gain, a feature that distinguishes it from other anti-psychotic drugs. Similarly, Geodon is unique among anti-psychotic drugs in that it does not increase cholesterol levels. 

Common side effects of Geodon include:

• feeling unusually tired,
• nausea,
• constipation,
• dizziness,
• restlessness,
• diarrhea, and
• rash.

Serious side effects of Geodon include:

• abnormal muscle movements (including tremor, shuffling, and uncontrollable movements),
• increased QT interval,
• serious changes heart rhythm (rare),
• dizziness or lightheadedness on standing,
• tardive dyskinesia (involuntary movements of the jaw, lips, and tongue), and
• neuroleptic malignant syndrome (NMS – symptoms include high fevers, muscle rigidity, altered mental status, irregular pulse or blood pressure, rapid heart rate, excessive sweating, and heart arrhythmias).

Drug interactions of Geodon include other drugs which also affect the QT interval such as:

• thioridazine,
• quinidine,
• moxifloxacin,
• pimozide,
• sotalol, dofetilide, and
• sparfloxacin, which can lead to serious heart rhythm disturbances.

Carbamazepine may lessen the effectiveness of Geodon.

The following may cause increases in levels of Geodon and more side effects:

• ketoconazole,
• itraconazole,
• fluconazole,
• erythromycin,
• clarithromycin,
• nefazodone,
• verapamil, and
• diltiazem.

Geodon has not been studied in pregnant women, but studies in animals have shown it causes birth defects. Physicians may choose to use Geodon if they feel its benefits outweigh this potential concern. It is unknown if Geodon is excreted in breast milk. Since most drugs are excreted in breast milk, it is recommended that women receiving Geodon do not breastfeed.

Some of the most common side effects associated with ziprasidone are:

• feeling unusually tired (1 in 7 patients),
• nausea (1 in 10),
• constipation (1 in 11),
• dizziness (1 in 12),
• restlessness (1 in 12), diarrhea (1 in 20), and
• rash (1 in 20).

Ziprasidone may cause a condition consisting of abnormal muscle movements, including tremor, shuffling, and uncontrollable movements (1 in 20 patients).

There is a slight risk (1 in 1500 patients) that ziprasidone by itself could significantly increase the QT interval. There is an even smaller risk (1 in 4000 patients) that it could cause a potentially serious change in the rhythm of the heart.

Ziprasidone causes orthostatic hypotension, a drop in blood pressure upon rising that can cause dizziness or lightheadedness. The risk is about 1 in 200 patients.

Ziprasidone frequently causes tiredness (1 in 7 patients). Therefore, care should be exercised in any activity requiring mental alertness, such as operating a motor vehicle (including automobiles) or operating hazardous machinery. Less common side effects include seizures (1 in 250 patients).

As with other antipsychotics, long-term use of ziprasidone may lead to a potentially irreversible condition called tardive dyskinesia (involuntary movements of the jaw, lips, and tongue).

A potentially fatal complex referred to as neuroleptic malignant syndrome (NMS) has been reported with other anti-psychotic drugs. Patients who develop NMS may have high fevers, muscle rigidity, altered mental status, irregular pulse or blood pressure, rapid heart rate, excessive sweating, and heart arrhythmias.

Although there is no clear link between ziprasidone and diabetes, patients should be tested during treatment for elevated blood-sugars.

• Additionally, persons with risk factors for diabetes, including obesity or a family history of diabetes, should have their fasting levels of blood sugar tested before starting treatment and periodically throughout treatment to detect the onset of diabetes.
• Any patient developing symptoms that suggest diabetes during treatment should be tested for diabetes.

Clinical Trials Experience

• Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
• Clinical trials for oral ziprasidone included approximately 5700 patients and/or normal subjects exposed to one or more doses of ziprasidone.
• Of these 5700, over 4800 were patients who participated in multiple-dose effectiveness trials, and their experience corresponded to approximately 1831 patient-years.
• These patients include:
  • (1) 4331 patients who participated in multiple-dose trials, predominantly in schizophrenia, representing approximately 1698 patient-years of exposure as of February 5, 2000; and
  • (2) 472 patients who participated in bipolar mania trials representing approximately 133 patient-years of exposure.
  • An additional 127 patients with bipolar disorder participated in a long-term maintenance treatment study representing approximately 74.7 patient-years of exposure to ziprasidone.
  • The conditions and duration of treatment with ziprasidone included open-label and double-blind studies, inpatient and outpatient studies, and short-term and longer-term exposure.
• Clinical trials for intramuscular ziprasidone included 570 patients and/or normal subjects who received one or more injections of ziprasidone. Over 325 of these subjects participated in trials involving the administration of multiple doses.
• Adverse reactions during exposure were obtained by collecting voluntarily reported adverse experiences, as well as results of physical examinations, vital signs, weights, laboratory analyses, ECGs, and results of ophthalmologic examinations.
• The stated frequencies of adverse reactions represent the proportion of individuals who experienced, at least once, a treatment-emergent adverse reaction of the type listed. A reaction was considered treatment emergent if it occurred for the first time or worsened while receiving therapy following baseline evaluation.

Adverse Findings Observed In Short-Term, Placebo-Controlled Trials With Oral Ziprasidone

The following findings are based on the short-term placebo-controlled premarketing trials for schizophrenia (a pool of two 6-week, and two 4-week fixed-dose trials) and bipolar mania (a pool of two 3-week flexible-dose trials) in which ziprasidone was administered in doses ranging from 10 to 200 mg/day.

Commonly Observed Adverse Reactions In Short Term-Placebo-Controlled Trials

The following adverse reactions were the most commonly observed adverse reactions associated with the use of ziprasidone (incidence of 5% or greater) and not observed at an equivalent incidence among placebo-treated patients (ziprasidone incidence at least twice that for placebo): Schizophrenia trials (see Table 11)

• Somnolence
• Respiratory Tract Infection Bipolar trials (see Table 12)
• Somnolence
• Extrapyramidal Symptoms which includes the following adverse reaction terms: extrapyramidal syndrome, hypertonia, dystonia, dyskinesia, hypokinesia, tremor, paralysis and twitching. None of these adverse reactions occurred individually at an incidence greater than 10% in bipolar mania trials.
• Dizziness which includes the adverse reaction terms dizziness and lightheadedness.
• Akathisia
• Abnormal Vision
• Asthenia
• Vomiting

Schizophrenia

• Adverse Reactions Associated with Discontinuation of Treatment in Short-Term, Placebo-Controlled Trials of Oral Ziprasidone
• Approximately 4.1% (29/702) of ziprasidone-treated patients in short-term, placebo-controlled studies discontinued treatment due to an adverse reaction, compared with about 2.2% (6/273) on placebo. The most common reaction associated with dropout was rash, including 7 dropouts for rash among ziprasidone patients (1%) compared to no placebo patients.
• Adverse Reactions Occurring at an Incidence of 2% or More Among Ziprasidone-Treated Patients in Short-Term, Oral, Placebo-Controlled Trials
• Table 11 enumerates the incidence, rounded to the nearest percent, of treatment-emergent adverse reactions that occurred during acute therapy (up to 6 weeks) in predominantly patients with schizophrenia, including only those reactions that occurred in 2% or more of patients treated with ziprasidone and for which the incidence in patients treated with ziprasidone was greater than the incidence in placebo-treated patients.

Table 11: Treatment-Emergent Adverse Reaction Incidence In Short-Term Oral Placebo-Controlled Trials – Schizophrenia

Dose Dependency Of Adverse Reactions In Short-Term, Fixed-Dose, Placebo-Controlled Trials

An analysis for dose response in the schizophrenia 4-study pool revealed an apparent relation of adverse reaction to dose for the following reactions:

• asthenia,
• postural hypotension,
• anorexia,
• dry mouth,
• increased salivation,
• arthralgia,
• anxiety,
• dizziness,
• dystonia,
• hypertonia,
• somnolence,
• tremor,
• rhinitis,
• rash, and
• abnormal vision.

Extrapyramidal Symptoms (EPS)

The incidence of reported EPS (which included the adverse reaction terms extrapyramidal syndrome, hypertonia, dystonia, dyskinesia, hypokinesia, tremor, paralysis and twitching) for ziprasidone-treated patients in the short-term, placebo-controlled schizophrenia trials was 14% vs. 8% for placebo. Objectively collected data from those trials on the Simpson-Angus Rating Scale (for EPS) and the Barnes Akathisia Scale (for akathisia) did not generally show a difference between ziprasidone and placebo.

Dystonia

Class Effect

Symptoms of dystonia, prolonged abnormal contractions of muscle groups, may occur in susceptible individuals during the first few days of treatment. Dystonic symptoms include:

• spasm of the neck muscles,
• sometimes progressing to tightness of the throat,
• swallowing difficulty,
• difficulty breathing, and/or protrusion of the tongue.

While these symptoms can occur at low doses, they occur more frequently and with greater severity with high potency and at higher doses of first generation antipsychotic drugs. An elevated risk of acute dystonia is observed in males and younger age groups.

Vital Sign Changes

Ziprasidone is associated with orthostatic hypotension

ECG Changes

Ziprasidone is associated with an increase in the QTc interval. In the schizophrenia trials, ziprasidone was associated with a mean increase in heart rate of 1.4 beats per minute compared to a 0.2 beats per minute decrease among placebo patients.

Other Adverse Reactions Observed During The Premarketing Evaluation Of Oral Ziprasidone

• Following is a list of COSTART terms that reflect treatment-emergent adverse reactions as defined in the prescribing information reported by patients treated with ziprasidone in schizophrenia trials at multiple doses >4 mg/day within the database of 3834 patients.
• All reported reactions are included except those already listed in Table 11 or elsewhere in labeling, those reaction terms that were so general as to be uninformative, reactions reported only once and that did not have a substantial probability of being acutely life-threatening, reactions that are part of the illness being treated or are otherwise common as background reactions, and reactions considered unlikely to be drug-related.
• It is important to emphasize that, although the reactions reported occurred during treatment with ziprasidone, they were not necessarily caused by it.
• Adverse reactions are further categorized by body system and listed in order of decreasing frequency according to the following definitions:
  • Frequent: adverse reactions occurring in at least 1/100 patients (≥1.0% of patients) (only those not already listed in the tabulated results from placebo-controlled trials appear in this listing);
  • Infrequent: adverse reactions occurring in 1/100 to 1/1000 patients (in 0.1-1.0% of patients)
  • Rare: adverse reactions occurring in fewer than 1/1000 patients (<0.1% of patients).

Body as a Whole

Frequent: abdominal pain, flu syndrome, fever, accidental fall, face edema, chills, photosensitivity reaction, flank pain, hypothermia, motor vehicle accident

Cardiovascular System

Frequent: tachycardia, hypertension, postural hypotension

Infrequent: bradycardia, angina pectoris, atrial fibrillation

Rare: first degree AV block, bundle branch block, phlebitis, pulmonary embolus, cardiomegaly, cerebral infarct, cerebrovascular accident, deep thrombophlebitis, myocarditis, thrombophlebitis

Digestive System

Frequent: anorexia, vomiting

Infrequent: rectal hemorrhage, dysphagia, tongue edema

Rare: gum hemorrhage, jaundice, fecal impaction, gamma glutamyl transpeptidase increased, hematemesis, cholestatic jaundice, hepatitis, hepatomegaly, leukoplakia of mouth, fatty liver deposit, melena

Endocrine

Rare: hypothyroidism, hyperthyroidism, thyroiditis

Hemic And Lymphatic System

Infrequent: anemia, ecchymosis, leukocytosis, leukopenia, eosinophilia, lymphadenopathy

Rare: thrombocytopenia, hypochromic anemia, lymphocytosis, monocytosis, basophilia, lymphedema, polycythemia, thrombocythemia

Metabolic And Nutritional Disorders

Infrequent: thirst, transaminase increased, peripheral edema, hyperglycemia, creatine phosphokinase increased, alkaline phosphatase increased, hypercholesteremia, dehydration, lactic dehydrogenase increased, albuminuria, hypokalemia

Rare: BUN increased, creatinine increased, hyperlipemia, hypocholesteremia, hyperkalemia, hypochloremia, hypoglycemia, hyponatremia, hypoproteinemia, glucose tolerance decreased, gout, hyperchloremia, hyperuricemia, hypocalcemia, hypoglycemicreaction, hypomagnesemia, ketosis, respiratory alkalosis

Musculoskeletal System

Frequent: myalgia Infrequent tenosynovitis

Rare: myopathy

Nervous System

Frequent: agitation, extrapyramidal syndrome, tremor, dystonia, hypertonia, dyskinesia, hostility, twitching, paresthesia, confusion, vertigo, hypokinesia, hyperkinesia, abnormal gait, oculogyric crisis, hypesthesia, ataxia, amnesia, cogwheel rigidity, delirium, hypotonia, akinesia, dysarthria, withdrawal syndrome, buccoglossal syndrome, choreoathetosis, diplopia, incoordination, neuropathy

Infrequent: paralysis

Rare: myoclonus, nystagmus, torticollis, circumoral paresthesia, opisthotonos, reflexes increased, trismus

Respiratory System

Frequent: dyspnea

Infrequent: pneumonia, epistaxis

Rare: hemoptysis, laryngismus

Skin And Appendages

Infrequent: maculopapular rash, urticaria, alopecia, eczema, exfoliative dermatitis, contact dermatitis, vesiculobullous rash

Special Senses

Frequent: fungal dermatitis

Infrequent: conjunctivitis, dry eyes, tinnitus, blepharitis, cataract, photophobia

Rare: eye hemorrhage, visual field defect, keratitis, keratoconjunctivitis

Urogenital System

Infrequent: impotence, abnormal ejaculation, amenorrhea, hematuria, menorrhagia, female lactation, polyuria, urinary retention metrorrhagia, male sexual dysfunction, anorgasmia, glycosuria

Rare: gynecomastia, vaginal hemorrhage, nocturia, oliguria, female sexual dysfunction, uterine hemorrhage

Biplar Disorder

Acute Treatment of Manic or Mixed Episodes

Adverse Reactions Associated with Discontinuation of Treatment in Short Term, Placebo-Controlled Trials

Approximately 6.5% (18/279) of ziprasidone-treated patients in short-term, placebo-controlled studies discontinued treatment due to an adverse reaction, compared with about 3.7% (5/136) on placebo. The most common reactions associated with dropout in the ziprasidone-treated patients were:

• akathisia,
• anxiety,
• depression,
• dizziness,
• dystonia,
• rash and
• vomiting.

There were 2 dropouts for each of these reactions among ziprasidone patients (1%) compared to one placebo patient each for dystonia and rash (1%) and no placebo patients for the remaining adverse reactions.

Adverse Reactions Occurring at an Incidence of 2% or More Among Ziprasidone-Treated Patients in Short-Term, Oral, Placebo-Controlled Trials

Table 12 enumerates the incidence, rounded to the nearest percent, of treatment-emergent adverse reactions that occurred during acute therapy (up to 3 weeks) in patients with bipolar mania, including only those reactions that occurred in 2% or more of patients treated with ziprasidone and for which the incidence in patients treated with ziprasidone was greater than the incidence in placebo-treated patients.

Table 12: Treatment-Emergent Adverse Reactions Incidence In Short-Term Oral Placebo-Controlled Trials – Manic and Mixed Episodes Associated with Bipolar Disorder

Explorations for interactions on the basis of gender did not reveal any clinically meaningful differences in the adverse reaction occurrence on the basis of this demographic factor.

Intramuscular Ziprasidone

Adverse Reactions Occurring at an Incidence of 1% or More Among Ziprasidone-Treated Patients in Short-Term Trials of Intramuscular Ziprasidone

Table 13 enumerates the incidence, rounded to the nearest percent, of treatment-emergent adverse reactions that occurred during acute therapy with intramuscular ziprasidone in 1% or more of patients.

In these studies, the most commonly observed adverse reactions associated with the use of intramuscular ziprasidone (incidence of 5% or greater) and observed at a rate on intramuscular ziprasidone (in the higher dose groups) at least twice that of the lowest intramuscular ziprasidone group were headache (13%), nausea (12%), and somnolence (20%).

Table 13: Treatment-Emergent Adverse Reaction Incidence In Short-Term Fixed-Dose Intramuscular Trials

Postmarketing Experience

The following adverse reactions have been identified during post-approval use of Geodon. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Adverse reaction reports not listed above that have been received since market introduction include rare occurrences of the following:

Cardiac Disorders: Tachycardia, torsade de pointes (in the presence of multiple confounding factors);
Digestive System Disorders: Swollen Tongue;
Reproductive System and Breast Disorders: Galactorrhea, priapism;
Nervous System Disorders: Facial Droop, neuroleptic malignant syndrome, serotonin syndrome (alone or in combination with serotonergic medicinal products), tardive dyskinesia;
Psychiatric Disorders: Insomnia, mania/hypomania;
Skin and subcutaneous Tissue Disorders: Allergic reaction (such as allergic dermatitis, angioedema, orofacial edema, urticaria), rash, Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS);
Urogenital System Disorders: Enuresis, urinary incontinence;
Vascular Disorders: Postural hypotension, syncope.

Drug-drug interactions can be pharmacodynamic (combined pharmacologic effects) or pharmacokinetic (alteration of plasma levels). The risks of using ziprasidone in combination with other drugs have been evaluated as described below. All interactions studies have been conducted with oral ziprasidone.

Based upon the pharmacodynamic and pharmacokinetic profile of ziprasidone, possible interactions could be anticipated:

Metabolic Pathway

• Approximately two-thirds of ziprasidone is metabolized via a combination of chemical reduction by glutathione and enzymatic reduction by aldehyde oxidase. There are no known clinically relevant inhibitors or inducers of aldehyde oxidase.
• Less than one-third of ziprasidone metabolic clearance is mediated by cytochrome P450 catalyzed oxidation.

In Vitro Studies

• An in vitro enzyme inhibition study utilizing human liver microsomes showed that ziprasidone had little inhibitory effect on CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A4, and thus would not likely interfere with the metabolism of drugs primarily metabolized by these enzymes.
• There is little potential for drug interactions with ziprasidone due to displacement.

Pharmacodynamic Interactions

• Ziprasidone should not be used with any drug that prolongs the QT interval.
• Given the primary CNS effects of ziprasidone, caution should be used when it is taken in combination with other centrally acting drugs.
• Because of its potential for inducing hypotension, ziprasidone may enhance the effects of certain antihypertensive agents.
• Ziprasidone may antagonize the effects of levodopa and dopamine agonists.

Pharmacokinetic Interactions

Carbamazepine

• Carbamazepine is an inducer of CYP3A4; administration of 200 mg twice daily for 21 days resulted in a decrease of approximately 35% in the AUC of ziprasidone. This effect may be greater when higher doses of carbamazepine are administered.

Ketoconazole

• Ketoconazole, a potent inhibitor of CYP3A4, at a dose of 400 mg QD for 5 days, increased the AUC and Cmax of ziprasidone by about 35-40%. Other inhibitors of CYP3A4 would be expected to have similar effects.

Cimetidine

• Cimetidine at a dose of 800 mg QD for 2 days did not affect ziprasidone pharmacokinetics.

Antacid

• The co-administration of 30 mL of Maalox with ziprasidone did not affect the pharmacokinetics of ziprasidone.

Lithium

• Ziprasidone at a dose of 40 mg twice daily administered concomitantly with lithium at a dose of 450 mg twice daily for 7 days did not affect the steady-state level or renal clearance of lithium. Ziprasidone dosed adjunctively to lithium in a maintenance trial of bipolar patients did not affect mean therapeutic lithium levels.

Oral Contraceptives

• In vivo studies have revealed no effect of ziprasidone on the pharmacokinetics of estrogen or progesterone components. Ziprasidone at a dose of 20 mg twice daily did not affect the pharmacokinetics of concomitantly administered oral contraceptives, ethinyl estradiol (0.03 mg) and levonorgestrel (0.15 mg).

Dextromethorphan

• Consistent with in vitro results, a study in normal healthy volunteers showed that ziprasidone did not alter the metabolism of dextromethorphan, a CYP2D6 model substrate, to its major metabolite, dextrorphan. There was no statistically significant change in the urinary dextromethorphan/dextrorphan ratio.

Valproate

• A pharmacokinetic interaction of ziprasidone with valproate is unlikely due to the lack of common metabolic pathways for the two drugs. Ziprasidone dosed adjunctively to valproate in a maintenance trial of bipolar patients did not affect mean therapeutic valproate levels.

Other Concomitant Drug Therapy

• Population pharmacokinetic analysis of schizophrenic patients enrolled in controlled clinical trials has not revealed evidence of any clinically significant pharmacokinetic interactions with benztropine, propranolol, or lorazepam.

Food Interaction

• The absolute bioavailability of a 20 mg dose under fed conditions is approximately 60%. The absorption of ziprasidone is increased up to two-fold in the presence of food.

Drug Abuse And Dependence

Dependence

• Ziprasidone has not been systematically studied, in animals or humans, for its potential for abuse, tolerance, or physical dependence.
• While the clinical trials did not reveal any tendency for drug-seeking behavior, these observations were not systematic and it is not possible to predict on the basis of this limited experience the extent to which ziprasidone will be misused, diverted, and/or abused once marketed.
• Consequently, patients should be evaluated carefully for a history of drug abuse, and such patients should be observed closely for signs of ziprasidone misuse or abuse (e.g., development of tolerance, increases in dose, drug-seeking behavior).