Torendo Q-Tab

Risperidone.

Each orodispersible tablet contains: TORENDO Q-Tab 1 mg: Risperidone: 1 mg.
TORENDO Q-Tab 2 mg: Risperidone: 2 mg.
Excipients/Inactive Ingredients: Mannitol, Basic butylated methacrylate copolymer, Povidone K25, Microcrystalline cellulose, Low substituted hydroxypropyl cellulose LH-21, Aspartame, Crospovidone, Red iron oxide E172, Spearmint flavour, Peppermint flavour, Calcium silicate, Magnesium stearate.

Pharmacology: Pharmacodynamics: Risperidone is an atypical antipsychotic of the benzisoxazole class (also known as a second generation antipsychotic). It is a selective antagonist of serotonin type 2 (5-HT2) and dopamine type 2 (D2) receptors. Risperidone binds also to alpha1-adrenergic receptors, and, with lower affinity, to H1-histaminergic and alpha2-adrenergic receptors. Risperidone has no affinity for cholinergic receptors. Although the drug is less likely to cause Parkinson's, dystonia and akathisia have occurred. According to the traditional hypothesis, antipsychotic drugs act through dopamine D2 receptor blockers and harmful extrapyramidal effects are also due to blockade of dopamine D2 receptors in the striatum. Like clozapine, risperidone has a high affinity for 5-HT2 receptors and like haloperidone, risperidone has a high affinity for dopamine D2 receptors. The exact mechanism of antipsychotic action is unknown, but appears to be much more complex than with most other antipsychotics. It is not clear whether the antipsychotic effect of risperidone is due to action on the dopamine D2 receptor or elsewhere. It is possible that some of the other potent effects of risperidone offset the activity of D2 to produce a "atypical drug" nature. Whereas typical antipsychotics are dopamine antagonists, the addition of serotonin (5-HT2) antagonists enhances efficacy for negative symptoms of schizophrenia and may reduce extrapyramidal symptoms. However, if the dose of risperidone exceeds 6 mg/kg/day, extrapyramidal effects are common. Risperidone has a sedative effect, so there may be interactions with analgesics and sedatives. In clinical studies, especially in people with schizophrenia, oral risperidone was at least as effective as typical (such as haloperidol) or atypical (such as olanzapine) antipsychotic agents, but risperidone was more effective than haloperidol in preventing relapse in outpatients after at least 1 year of treatment with either agent. Risperidone is particularly useful in patients already taking typical antipsychotics who experience extrapyramidal reactions because risperidone is less likely to cause this reaction. In the elderly with dementia, risperidone increases the risk of stroke.
Pharmacokinetics: Torendo Q-Tab orodispersible tablets are bio-equivalent to Torendo Q-Tab film-coated tablets.
Risperidone is metabolised to 9-hydroxy-risperidone, which has a similar pharmacological activity to risperidone.
Risperidone is well absorbed after oral administration. Food does not affect the rate or extent of absorption. Risperidone is extensively metabolized in the liver by cytochrome P450 II D6 catalysis to the major, active metabolite, 9-hydroxy-risperidone. It is as potent as risperidone in terms of receptor-binding activity and has a half-life of 20 ± 3 hours. Following oral administration of risperidone, peak plasma concentrations are reached within 1 hour. Oral bioavailability is 66 ± 28% in strong metabolizers and higher in weak metabolizers. Plasma protein binding was 89% for risperidone and 77% for the active metabolite. The volume of distribution of risperidone is 1-2 liters/kg. In extensive metabolisers, the half-life of risperidone was 3.2 ± 0.8 hours, the urinary excretion was 3 ± 2%, and the clearance was 5.5 ± 2 ml/min/kg. The active metabolite, 9-hydroxyrisperidone has a half-life of 20 ± 3 hours. The drug is eliminated mainly in the urine and to a lesser extent in the faeces. Risperidone and its metabolite 9-hydroxyrisperidone both pass into breast milk.

Psychotic disorders, especially acute and chronic schizophrenia.
Short-term treatment of moderate to severe acute manic episodes.
Autism with behavioral disorders in children aged 5-11 years.

Method of administration: Risperidone: Take one daily or twice daily. Taken on full or empty stomach, food does not affect the gastrointestinal absorption of risperidone. If drowsy, drink 1 time at bedtime. Remove the tablet from the blister, immediately place it on the tongue, do not need to drink with water.
Or drop the tablet into a glass of water, and drink immediately.
Posology: Schizophrenia: Adults, the first dose on the first day: 2 mg orally once or twice a day.
The second day: 4 mg orally once or twice a day.
The third day: 6 mg orally once or twice a day.
From 4^th day, the maintenance dose will unchange or adjust according to the patient as needed.
Usual optimal dosage: 4-8 mg/day orally once or twice a day. However, recent clinical experience has shown that the more appropriate dose for the treatment of the majority of healthy patients with schizophrenia is as follows: Initial dose 1-2 mg/day, gradually increasing daily dose to 0.5-1 mg over 6-7 days, if tolerated, to target dose of 4 mg/day. Dosage adjustments must be made at least 7 days apart.
For young adults and for first-timers, the initial dose may be lower (eg, 1 mg/day) and titrated more slowly up to the first target dose of 2 mg/day; The dose may then be titrated up to 4 mg/day according to clinical response to achieve the smallest effective dose. These patients usually have an optimal dose of risperidone 1 to 3 mg/day. Some patients on first-line therapy began to have extrapyramidal symptoms once the dose was increased above 2 mg/day. Dosage should be reduced at the onset of extrapyramidal symptoms.
Patients need to be evaluated periodically to decide whether to continue treatment.
Bipolar disease: Treatment of manic and mixed episodes of bipolar disease: Take the first dose of 2-3 mg orally once daily. The dose may be increased or decreased by 1 mg/day at intervals of not less than 24 hours.
If treatment exceeds 3 weeks, periodically assess the risks of prolonged therapy and the benefits of the drug for each patient.
Autism with behavioral disorders in children aged 5 years and older: The first dose is 0.25 mg/day for children weighing less than 20 kg and 0.5 mg/day for children weighing 20 kg or more. The drug can be given once or twice a day. Dosage is adjusted according to the response and tolerability of each patient. At least 4 days after the first dose, the dose may be increased to the recommended dose of 0.5 mg/day for children weighing <20 kg and 1 mg/day for children weighing 20 kg or more. Then this dose is maintained for a minimum of 14 days. For patients who do not respond satisfactorily, the dose may be increased at intervals of 2 weeks or more in increments of 0.25 mg/day for patients weighing <20 kg or 0.5 mg/day for those patients weighing 20 kg or more.
Dosage in renal and hepatic impairment, the elderly, or those at risk for orthostatic hypotension: Because the elimination of risperidone may be reduced and the risk of adverse effects, especially orthostatic hypotension, is increased in patients with renal impairment and in the elderly, risperidone therapy should be initiated at a reduced dose, 0.5 mg, once or twice a day and increased as needed and as tolerated, in increments not exceeding 0.5 mg, twice daily; Dose increases beyond 1.5 mg, twice daily, must be done at an interval of at least 7 days. Some clinicians recommend an initial dose of 0.25 mg/day and gradually increased as tolerated in the elderly. The dose should not be maintained in excess of 3 mg/day in the elderly. Dosage reduction is also required in patients with hepatic impairment because of the increased risk of free risperidone in these patients.

Symptoms: In general, reported signs and symptoms have been those resulting from an exaggeration of the known pharmacological effects of risperidone. These include drowsiness and sedation, tachycardia and hypotension. Other effects include QT prolongation and convulsions, and cardiac-respiratory arrest.
Treatment: Establish and maintain a clear airway and ensure adequate oxygenation and ventilation. Gastric lavage (after intubation, if the patient loses consciousness) and Administration of activated charcoal. Impaired consciousness, seizures, or dystonia of the head and neck following overdose may pose a risk of aspiration of vomit during vomiting. Cardiovascular monitoring should commence immediately and should include continuous electrocardiographic monitoring to detect possible arrhythmias. If antiarrhythmic therapy is to be used, disopyramide, procainamide and quinidine should not be used, as they also cause QT prolongation, in addition to the effects of risperidone. The alpha adrenergic blocking effects of bretylium are also combined with those of risperidone leading to hypotension. Therefore, antiarrhythmic drugs other than those previously mentioned should be used. There is no specific antidote to risperidone. Therefore, appropriate supportive measures should be instituted. Hypotension and circulatory collapse should be treated with appropriate measures such as intravenous fluids and/or sympathomimetic agents (Do not use epinephrine and dopamine, because beta stimulation may increase hypotension caused by the alpha-blocking effect of risperidone). In case of severe extrapyramidal symptoms, an anticholinergic medicinal product should be administered. Close medical supervision and monitoring should continue until the patient recovers.

The patient overdosed on barbiturates, opiate preparations or alcohol.
History of hypersensitivity to any ingredient of the drug.

The risk of orthostatic hypotension and syncope during treatment with risperidone can be minimized by limiting the initial dose to 1 mg twice daily for normal adults and 0.5 mg twice daily, for the elderly or debilitated, those with impaired renal or hepatic function and those prone to or at risk of hypotension.
In patients with cardiovascular disease (severe arteriosclerosis, heart failure, conduction disturbances), cerebrovascular disease, or conditions predisposed to hypotension (eg, dehydration, decreased blood flow, concomitant antihypertensive therapy) and in patients with a history of seizures, spasticity or Parkinson's syndrome, a lower dose should be used and treatment should be initiated at a low dose. Because risperidone can interfere with judgment, thinking and motor skills, patients should not operate hazardous machinery, including motor vehicles, until they are certain that risperidone is not causing the undesirable effects as previously mentioned. People with diabetes or people at high risk of diabetes (fat, family history of diabetes, etc) when taking any atypical drug including risperidone must closely monitor blood glucose.
People with Parkinson's syndrome or dementia taking antipsychotics including risperidone may increase their sensitivity to antipsychotics. Clinical manifestations: Confusion, loss of balance, easy to fall, extrapyramidal symptoms. Close monitoring is required.
Use with caution in patients with a history of convulsions.
Caution should be exercised when giving drugs to elderly people with dementia because of the risk of aspiration into the lungs.
Drugs used for children, must monitor weight, drugs that increase prolactin secretion. The manufacturer states that the long-term effects of risperidone on a child's development and maturation are not fully known.
Effects on Ability to Drive and Use Machines: Use caution when driving and using machines.

Do not use risperidone in pregnancy.
People who are taking risperidone should not breast-feed.

Common undesirable effects during treatment with risperidone are anxiety, drowsiness, extrapyramidal symptoms, dizziness, constipation, nausea, dyspepsia, rhinitis, rash and tachycardia.
Common undesirable effects when stopping the drug include extrapyramidal symptoms, dizziness, hyperactivity, drowsiness and nausea.
Common, ADR >1/100: Central nervous system: Dizziness, hyperactivity, anxiety, drowsiness, extrapyramidal symptoms, headache, Parkinson's syndrome.
Digestive: Constipation, nausea, vomiting, dyspepsia, abdominal pain, anorexia, increased salivation, toothache.
Respiratory: Rhinitis, cough, sinusitis, pharyngitis, dyspnea.
Skin: Rash, dry skin, increased sebum secretion.
Neurologic - musculoskeletal - joint: Arthralgia.
Cardiovascular: Tachycardia, postural hypotension.
Eye: Blurred vision.
Others: Back pain, chest pain, fever, fatigue, upper respiratory tract infection, sexual dysfunction.
Rare, ADR <1/1000: Central nervous system: Decreased concentration, depression, apathy, hypertonic reactions, euphoria, increased libido, amnesia, dysarthria, dizziness, stupor, paresthesia, confusion.
Digestive: Flatulence, diarrhea, increased appetite, stomatitis, melena, dysphagia, hemorrhoids, gastritis.
Respiratory: Tachypnea, bronchospasm, pneumonia, wheezing.
Skin: Increased or decreased sweating, acne, hair loss.
Cardiovascular: Hypertension, hypotension, edema, atrioventricular block, myocardial infarction.
Eyes: Accommodation disorder, dry eyes.
Endocrine and metabolic: Hyponatremia, weight gain or loss, increased creatine phosphokinase, thirst, diabetes mellitus, non-constipation galactorrhea, amenorrhea, dysmenorrhea, gynecomastia.
Urogenital: Bedwetting, hematuria, dysuria, female breast pain, intermenstrual bleeding, vaginal bleeding.
Hematologic: Epistaxis, purpura, anemia.
Other: Chills, malaise, flu-like symptoms.
Inform the doctor of any undesirable effects the patient may experience while taking the medication.

Quinidine may potentiate the atrioventricular-blocking effect of risperidone.
Risperidone may enhance the antihypertensive effect of antihypertensive drugs. Risperidone may antagonize the effects of levodopa and dopamine agonists. The long-term use of carbamazepine in combination with risperidone may potentiate the effects of risperidone. The use of clozapine with risperidone may increase the effects of risperidone. Because of the predominant central nervous system effects of risperidone, lower doses of risperidone must be used in combination with other centrally-acting drugs and alcohol. In all these cases, the dose should be adjusted.

Store in a dry place, protected from light and moisture, below 30°C.
Shelf Life: 36 months from the date of manufacture.

Antipsychotics

N05AX08 - risperidone ; Belongs to the class of other antipsychotics.