Thursday, September 8, 2016

Topiramate 200mg Film-Coated Tablets





1. Name Of The Medicinal Product



Topiramate 200mg Film-Coated Tablets


2. Qualitative And Quantitative Composition



Each tablet contains 200mg of Topiramate.



Excipient: Also contains 1.06mg soya lecithin (E322).



For a full list of excipients, see section 6.1.



3. Pharmaceutical Form



Film-Coated Tablets



Topiramate 200mg Film-Coated Tablets are salmon, oval, biconvex tablets with 9.2-18.3mm dimensions and engraved with the marking “V5”.



4. Clinical Particulars



4.1 Therapeutic Indications



Monotherapy in adults, adolescents and children over 6 years of age with partial seizures with or without secondary generalised seizures, and primary generalised tonic-clonic seizures.



Adjunctive therapy in children aged 2 years and above, adolescents and adults with partial onset seizures with or without secondary generalization or primary generalized tonic-clonic seizures and for the treatment of seizures associated with Lennox-Gastaut syndrome.



Topiramate is indicated in adults for the prophylaxis of migraine headache after careful evaluation of possible alternative treatment options. Topiramate is not intended for acute treatment.



4.2 Posology And Method Of Administration



General



It is recommended that therapy be initiated at a low dose followed by titration to an effective dose. Dose and titration rate should be guided by clinical response.



Topiramate is available in film-coated tablets and it is recommended that the film-coated tablets not be broken.



It is not necessary to monitor topiramate plasma concentrations to optimize therapy with topiramate. On rare occasions, the addition of topiramate to phenytoin may require an adjustment of the dose of phenytoin to achieve optimal clinical outcome. Addition or withdrawal of phenytoin and carbamazepine to adjunctive therapy with topiramate may require adjustment of the dose of topiramate.



Topiramate can be taken without regard to meals.



In patients with or without a history of seizures or epilepsy, antiepileptic drugs including topiramate should be gradually withdrawn to minimize the potential for seizures or increased seizure frequency. In clinical trials, daily dosages were decreased in weekly intervals by 50-100 mg in adults with epilepsy and by 25-50 mg in adults receiving topiramate at doses up to 100 mg/day for migraine prophylaxis. In paediatric clinical trials, topiramate was gradually withdrawn over a 2-8 week period.



Monotherapy epilepsy



General



When concomitant antiepileptic drugs (AEDs) are withdrawn to achieve monotherapy with topiramate, consideration should be given to the effects this may have on seizure control. Unless safety concerns require an abrupt withdrawal of the concomitant AED, a gradual discontinuation at the rate of approximately one-third of the concomitant AED dose every 2 weeks is recommended.



When enzyme inducing medicinal products are withdrawn, topiramate levels will increase. A decrease in topiramate dosage may be required if clinically indicated.



Adults



Dose and titration should be guided by clinical response. Titration should begin at 25 mg nightly for 1 week. The dosage should then be increased at 1- or 2-week intervals by increments of 25 or 50 mg/day, administered in two divided doses. If the patient is unable to tolerate the titration regimen, smaller increments or longer intervals between increments can be used.



The recommended initial target dose for topiramate monotherapy in adults is 100 mg/day to 200 mg/day in 2 divided doses. The maximum recommended daily dose is 500 mg/day in 2 divided doses. Some patients with refractory forms of epilepsy have tolerated topiramate monotherapy at doses of 1,000 mg/day. These dosing recommendations apply to all adults including the elderly in the absence of underlying renal disease.



Paediatric population (children over 6 years of age)



Dose and titration rate in children should be guided by clinical outcome. Treatment of children over 6 years of age should begin at 0.5 to 1 mg/kg nightly for the first week. The dosage should then be increased at 1 or 2 week intervals by increments of 0.5 to 1 mg/kg/day, administered in two divided doses. If the child is unable to tolerate the titration regimen, smaller increments or longer intervals between dose increments can be used.



The recommended initial target dose range for topiramate monotherapy in children over 6 years of age is 100 mg/day depending on clinical response, (this is about 2.0 mg/kg/day in children 6-16 years).



Adjunctive therapy epilepsy (partial onset seizures with or without secondary generalization, primary generalized tonic-clonic seizures, or seizures associated with Lennox-Gastaut syndrome)



Adults



Therapy should begin at 25-50 mg nightly for one week. Use of lower initial doses has been reported, but has not been studied systematically. Subsequently, at weekly or bi-weekly intervals, the dose should be increased by 25-50 mg/day and taken in two divided doses. Some patients may achieve efficacy with once-a-day dosing.



In clinical trials as adjunctive therapy, 200 mg was the lowest effective dose. The usual daily dose is 200-400 mg in two divided doses.



These dosing recommendations apply to all adults, including the elderly, in the absence of underlying renal disease (see section 4.4).



Paediatric population (children aged 2 years and above)



The recommended total daily dose of topiramate as adjunctive therapy is approximately 5 to 9 mg/kg/day in two divided doses. Titration should begin at 25 mg (or less, based on a range of 1 to 3 mg/kg/day) nightly for the first week. The dosage should then be increased at 1- or 2-week intervals by increments of 1 to 3 mg/kg/day (administered in two divided doses), to achieve optimal clinical response.



Daily doses up to 30 mg/kg/day have been studied and were generally well tolerated.



Migraine



Adults



The recommended total daily dose of topiramate for prophylaxis of migraine headache is 100 mg/day administered in two divided doses. Titration should begin at 25 mg nightly for 1 week. The dosage should then be increased in increments of 25 mg/day administered at 1-week intervals. If the patient is unable to tolerate the titration regimen, longer intervals between dose adjustments can be used.



Some patients may experience a benefit at a total daily dose of 50 mg/day. Patients have received a total daily dose up to 200 mg/day. This dose may be benefit in some patients, nevertheless, caution is advised due to an increase incidence of side effects



Paediatric population



Topiramate is not recommended for treatment or prevention of migraine in children due to insufficient data on safety and efficacy.



General dosing recommendations for topiramate in special patient populations



Renal impairment



In patients with impaired renal function (CLCR



In patients with end-stage renal failure, since topiramate is removed from plasma by haemodialysis, a supplemental dose of topiramate equal to approximately one-half the daily dose should be administered on haemodialysis days. The supplemental dose should be administered in divided doses at the beginning and completion of the haemodialysis procedure. The supplemental dose may differ based on the characteristics of the dialysis equipment being used.



Hepatic impairment



In patients with moderate to severe hepatic impairment topiramate should be administered with caution as the clearance of topiramate is decreased.



Elderly



No dose adjustment is required in the elderly population providing renal function is intact.



4.3 Contraindications



Hypersensitivity to the active substance or to any of the excipients.



Migraine prophylaxis in pregnancy and in women of childbearing potential if not using effective methods of contraception



4.4 Special Warnings And Precautions For Use



In situations where rapid withdrawal of topiramate is medically required, appropriate monitoring is recommended (see section 4.2 for further details).



As with other anti-epileptic drugs, some patients may experience an increase in seizure frequency or the onset of new types of seizures with topiramate. These phenomena may be the consequence of an overdose, a decrease in plasma concentrations of concomitantly used anti-epileptics, progress of the disease, or a paradoxical effect.



Adequate hydration while using topiramate is very important. Hydration can reduce the risk of nephrolithiasis (see below). Proper hydration prior to and during activities such as exercise or exposure to warm temperatures may reduce the risk of heat-related adverse reactions (see section 4.8).



Oligohydrosis (decreased sweating) has been reported in association with the use of topiramate. Decreased sweating and rise in body temperature may occur especially in young children exposed to high ambient temperature.



Mood disturbances/depression



An increased incidence of mood disturbances and depression has been observed during topiramate treatment.



Suicide/suicide ideation



Suicidal ideation and behaviour have been reported in patients treated with anti-epileptic agents in several indications. A meta-analysis of randomised placebo-controlled trials of anti-epileptic drugs has shown a small increased risk of suicidal ideation and behaviour. The mechanism of this risk is not known and the available data do not exclude the possibility of an increased risk for topiramate.



In double blind clinical trials, suicide related events (SREs) (suicidal ideation, suicide attempts and suicide) occurred at a frequency of 0.5 % in topiramate treated patients (46 out of 8,652 patients treated) and at a nearly 3 fold higher incidence than those treated with placebo (0.2 %; 8 out of 4,045 patients treated).



Patients therefore should be monitored for signs of suicidal ideation and behaviour and appropriate treatment should be considered. Patients (and caregivers of patients) should be advised to seek medical advice should signs of suicidal ideation or behaviour emerge.



Nephrolithiasis



Some patients, especially those with a predisposition to nephrolithiasis, may be at increased risk for renal stone formation and associated signs and symptoms such as renal colic, renal pain or flank pain.



Risk factors for nephrolithiasis include prior stone formation, a family history of nephrolithiasis and hypercalciuria. None of these risk factors can reliably predict stone formation during topiramate treatment. In addition, patients taking other medicinal products associated with nephrolithiasis may be at increased risk.



Decreased hepatic function



In hepatically-impaired patients, topiramate should be administered with caution as the clearance of topiramate may be decreased.



Acute myopia and secondary angle closure glaucoma



A syndrome consisting of acute myopia associated with secondary angle closure glaucoma has been reported in patients receiving topiramate. Symptoms include acute onset of decreased visual acuity and/or ocular pain. Ophthalmologic findings can include myopia, anterior chamber shallowing, ocular hyperaemia (redness) and increased intraocular pressure. Mydriasis may or may not be present. This syndrome may be associated with supraciliary effusion resulting in anterior displacement of the lens and iris, with secondary angle closure glaucoma. Symptoms typically occur within 1 month of initiating topiramate therapy. In contrast to primary narrow angle glaucoma, which is rare under 40 years of age, secondary angle closure glaucoma associated with topiramate has been reported in paediatric patients as well as adults. Treatment includes discontinuation of topiramate, as rapidly as possible in the judgment of the treating physician, and appropriate measures to reduce intraocular pressure. These measures generally result in a decrease in intraocular pressure.



Elevated intraocular pressure of any aetiology, if left untreated, can lead to serious sequelae including permanent vision loss.



A determination should be made whether patients with history of eye disorders should be treated with topiramate.



Metabolic acidosis



Hyperchloremic, non-anion gap, metabolic acidosis (i.e. decreased serum bicarbonate below the normal reference range in the absence of respiratory alkalosis) is associated with topiramate treatment. Depending on underlying conditions, appropriate evaluation including measurement of serum bicarbonate levels is recommended with topiramate therapy. If signs or symptoms are present (e.g. Kussmaul's deep breathing, dyspnoea, anorexia, nausea, vomiting, excessive tiredness, tachycardia or arrhythmia), indicative of metabolic acidosis, measurement of serum bicarbonate is recommended. If metabolic acidosis develops and persists, consideration should be given to reducing the dose or discontinuing topiramate (using dose tapering).



This decrease in serum bicarbonate is due to the inhibitory effect of topiramate on renal carbonic anhydrase. Generally, the decrease in bicarbonate occurs early in treatment although it can occur at any time during treatment. These decreases are usually mild to moderate (average decrease of 4 mmol/l at doses of 100 mg/day or above in adults and at approximately 6 mg/kg/day in paediatric patients). Rarely, patients have experienced decreases to values below 10 mmol/l. Conditions or therapies that predispose to acidosis (such as renal disease, severe respiratory disorders, status epilepticus, diarrhoea, surgery, ketogenic diet, or certain medicinal products) may be additive to the bicarbonate lowering effects of topiramate.



Chronic metabolic acidosis increases the risk of renal stone formation and may potentially lead to osteopenia.



Chronic metabolic acidosis in paediatric patients can reduce growth rates. The effect of topiramate on bone-related sequelae has not been systematically investigated in paediatric or adult populations.



Depending on underlying conditions, appropriate evaluation including serum bicarbonate levels is recommended with topiramate therapy. If metabolic acidosis develops and persists, consideration should be given to reducing the dose or discontinuing topiramate (using dose tapering).



Topiramate should be used with caution in patients with conditions or treatments that represent a risk factor for the appearance of metabolic acidosis.



Nutritional supplementation



Some patients may experience weight loss whilst on treatment with topiramate. It is recommended that patients on topiramate treatment should be monitored for weight loss. A dietary supplement or increased food intake may be considered if the patient is losing weight while on topiramate.



Lecithin



Topiramate 50 mg, 100 mg and 200 mg film-coated tablets contain lecithin (contains soya oil). Patients that are allergic to peanuts or soya should not use this medicinal product.



Impairment of cognitive function



Cognitive impairment in epilepsy is multifactorial and may be due to the underlying aetiology, due to the epilepsy or due to the anti epileptic treatment. There have been reports in the literature of impairment of cognitive function in adults on topiramate therapy which required reduction in dosage or discontinuation of treatment. However, studies regarding cognitive outcomes in children treated with topiramate are insufficient and its effect in this regard still needs to be elucidated.



4.5 Interaction With Other Medicinal Products And Other Forms Of Interaction



Effects of topiramate on other antiepileptic medicinal products



The addition of topiramate to other antiepileptic drugs (phenytoin, carbamazepine, valproic acid, phenobarbital, primidone) has no effect on their steady-state plasma concentrations, except in the occasional patient, where the addition of topiramate to phenytoin may result in an increase of plasma concentrations of phenytoin. This is possibly due to inhibition of a specific enzyme polymorphic isoform (CYP2C19). Consequently, any patient on phenytoin showing clinical signs or symptoms of toxicity should have phenytoin levels monitored.



A pharmacokinetic interaction study of patients with epilepsy indicated the addition of topiramate to lamotrigine had no effect on steady state plasma concentration of lamotrigine at topiramate doses of 100 to 400 mg/day. In addition, there was no change in steady state plasma concentration of topiramate during or after removal of lamotrigine treatment (mean dose of 327 mg/day).



Topiramate inhibits the enzyme CYP 2C19 and may interfere with other substances metabolized via this enzyme (e.g., diazepam, imipramin, moclobemide, proguanil, omeprazol).



Effects of other antiepileptic medicinal products on topiramate



Phenytoin and carbamazepine decrease the plasma concentration of topimarate. The addition or withdrawal of phenytoin or carbamazepine to topiramate therapy may require an adjustment in dosage of the latter. This should be done by titrating to clinical effect. The addition or withdrawal of valproic acid does not produce clinically significant changes in plasma concentrations of topiramate and, therefore, does not warrant dosage adjustment of topiramate. The results of these interactions are summarized below:




























AED Coadministered




AED Concentration




Topiramate Concentration




Phenytoin




↔**







Carbamazepine (CBZ)




↔ 







Valproic acid




↔ 




↔ 




Lamotrigine




↔ 




↔ 




Phenobarbital




↔ 




NS




Primidone




↔ 




NS




↔ = No effect on plasma concentration (



** = Plasma concentrations increase in individual patients





NS = Not studied



AED = antiepileptic drug


  


Other medicinal product interactions



Digoxin



In a single-dose study, serum digoxin area under plasma concentration curve (AUC) decreased 12 % due to concomitant administration of topiramate. The clinical relevance of this observation has not been established. When topiramate is added or withdrawn in patients on digoxin therapy, careful attention should be given to the routine monitoring of serum digoxin.



CNS depressants



Concomitant administration of topiramate and alcohol or other CNS depressant medicinal products has not been evaluated in clinical studies. It is recommended that topiramate not be used concomitantly with alcohol or other CNS depressant medicinal products.



St John's Wort (Hypericum perforatum)



A risk of decreased plasma concentrations resulting in a loss of efficacy could be observed with co-administration of topiramate and St John's Wort. There have been no clinical studies evaluating this potential interaction.



Oral contraceptives



In a pharmacokinetic interaction study in healthy volunteers with a concomitantly administered combination oral contraceptive product containing 1 mg norethindrone (NET) plus 35 μg ethinyl estradiol (EE), topiramate given in the absence of other medications at doses of 50 to 200 mg/day was not associated with statistically significant changes in mean exposure (AUC) to either component of the oral contraceptive. In another study, exposure to EE was statistically significantly decreased at doses of 200, 400, and 800 mg/day (18 %, 21 %, and 30 %, respectively) when given as adjunctive therapy in epilepsy patients taking valproic acid. In both studies, topiramate (50-200 mg/day in healthy volunteers and 200-800 mg/day in epilepsy patients) did not significantly affect exposure to NET. Although there was a dose dependent decrease in EE exposure for doses between 200-800 mg/day (in epilepsy patients), there was no significant dose dependent change in EE exposure for doses of 50-200 mg/day (in healthy volunteers). The clinical significance of the changes observed is not known. The possibility of decreased contraceptive efficacy and increased breakthrough bleeding should be considered in patients taking combination oral contraceptive products with topiramate. Patients taking estrogen containing contraceptives should be asked to report any change in their bleeding patterns. Contraceptive efficacy can be decreased even in the absence of breakthrough bleeding.



Lithium



In healthy volunteers, there was an observed reduction (18 % for AUC) in systemic exposure for lithium during concomitant administration with topiramate 200 mg/day. In patients with bipolar disorder, the pharmacokinetics of lithium were unaffected during treatment with topiramate at doses of 200 mg/day; however, there was an observed increase in systemic exposure (26 % for AUC) following topiramate doses of up to 600 mg/day. Lithium levels should be monitored when co-administered with topiramate.



Risperidone



Drug-drug interaction studies conducted under single dose conditions in healthy volunteers and multiple dose conditions in patients with bipolar disorder, yielded similar results. When administered concomitantly with topiramate at escalating doses of 100, 250 and 400 mg/day there was a reduction in risperidone (administered at doses ranging from 1 to 6 mg/day) systemic exposure (16 % and 33 % for steady-state AUC at the 250 and 400 mg/day doses, respectively). However, differences in AUC for the total active moiety between treatment with risperidone alone and combination treatment with topiramate were not statistically significant. Minimal alterations in the pharmacokinetics of the total active moiety (risperidone plus 9-hydroxyrisperidone) and no alterations for 9-hydroxyrisperidone were observed. There were no significant changes in the systemic exposure of the risperidone total active moiety or of topiramate. When topiramate was added to existing risperidone (1-6 mg/day) treatment, adverse events were reported more frequently than prior to topiramate (250-400 mg/day) introduction (90 % and 54 % respectively). The most frequently reported AE's when topiramate was added to risperidone treatment were: somnolence (27 % and 12 %), paraesthesia (22 % and 0 %) and nausea (18 % and 9 % respectively).



Hydrochlorothiazide (HCTZ)



A drug-drug interaction study conducted in healthy volunteers evaluated the steady-state pharmacokinetics of HCTZ (25 mg q24h) and topiramate (96 mg q12h) when administered alone and concomitantly. The results of this study indicate that topiramate Cmax increased by 27 % and AUC increased by 29 % when HCTZ was added to topiramate. The clinical significance of this change is unknown. The addition of HCTZ to topiramate therapy may require an adjustment of the topiramate dose. The steady-state pharmacokinetics of HCTZ were not significantly influenced by the concomitant administration of topiramate. Clinical laboratory results indicated decreases in serum potassium after topiramate or HCTZ administration, which were greater when HCTZ and topiramate were administered in combination.



Metformin



A drug-drug interaction study conducted in healthy volunteers evaluated the steady-state pharmacokinetics of metformin and topiramate in plasma when metformin was given alone and when metformin and topiramate were given simultaneously. The results of this study indicated that metformin mean Cmax and mean AUC0-12h increased by 18 % and 25 %, respectively, while mean CL/F decreased 20 % when metformin was co-administered with topiramate. Topiramate did not affect metformin tmax. The clinical significance of the effect of topiramate on metformin pharmacokinetics is unclear. Oral plasma clearance of topiramate appears to be reduced when administered with metformin. The extent of change in the clearance is unknown. The clinical significance of the effect of metformin on topiramate pharmacokinetics is unclear.



When topiramate is added or withdrawn in patients on metformin therapy, careful attention should be given to the routine monitoring for adequate control of their diabetic disease state.



Pioglitazone



A drug-drug interaction study conducted in healthy volunteers evaluated the steady-state pharmacokinetics of topiramate and pioglitazone when administered alone and concomitantly. A 15 % decrease in the AUCmax,ss was observed. This finding was not statistically significant. In addition, a 13 % and 16 % decrease in Cmax,ss and AUCmax,ss and AUC



Glyburide



A drug-drug interaction study conducted in patients with type 2 diabetes evaluated the steady-state pharmacokinetics of glyburide (5 mg/day) alone and concomitantly with topiramate (150 mg/day). There was a 25 % reduction in glyburide AUC24 during topiramate administration. Systemic exposure of the active metabolites, 4-trans-hydroxy-glyburide (M1) and 3-cis-hydroxyglyburide (M2), were also reduced by 13 % and 15 %, respectively. The steady-state pharmacokinetics of topiramate were unaffected by concomitant administration of glyburide.



When topiramate is added to glyburide therapy or glyburide is added to topiramate therapy, careful attention should be given to the routine monitoring of patients for adequate control of their diabetic disease state.



Other forms of interactions



Agents predisposing to nephrolithiasis



Topiramate, when used concomitantly with other agents predisposing to nephrolithiasis, may increase the risk of nephrolithiasis. While using topiramate, agents like these should be avoided since they may create a physiological environment that increases the risk of renal stone formation.



Valproic acid



Concomitant administration of topiramate and valproic acid has been associated with hyperammonemia with or without encephalopathy in patients who have tolerated either medicinal product alone. In most cases, symptoms and signs abated with discontinuation of either medicinal product. This adverse reaction is not due to a pharmacokinetic interaction. An association of hyperammonemia with topiramate monotherapy or concomitant treatment with other anti-epileptics has not been established.



Additional pharmacokinetic drug interaction studies



Clinical studies have been conducted to assess the potential pharmacokinetic drug interaction between topiramate and other agents. The changes in Cmax or AUC as a result of the interactions are summarized below. The second column (concomitant drug concentration) describes what happens to the concentration of the concomitant drug listed in the first column when topiramate is added. The third column (topiramate concentration) describes how the coadministration of a drug listed in the first column modifies the concentration of topiramate.








































Summary of Results from Additional Clinical Pharmacokinetic Drug Interaction Studies


  


Concomitant Drug




Concomitant Drug Concentrationa




Topiramate Concentrationa




Amitriptyline




↔ 20 % increase in Cmax and AUC of nortriptyline metabolite




NS




Dihydroergotamine (Oral and Subcutaneous)




↔ 




↔ 




Haloperidol




↔ 31 % increase in AUC of the reduced metabolite




NS




Propranolol




↔ 17 % increase in Cmax for 4-OH propranolol (TPM 50 mg q12h)




9 % and 16 % increase in Cmax,



9 % and17 % increase in AUC (40 and 80 mg propranolol q12h respectively)




Sumatriptan (Oral and Subcutaneous)




↔ 




NS




Pizotifen




↔ 




↔ 




Diltiazem




25 % decrease in AUC of diltiazem and 18 % decrease in DEA, and ↔ for DEM*




20 % increase in AUC




Venlafaxine




↔ 




↔ 




Flunarizine




16 % increase in AUC



(TPM 50 mg q12h)b




↔ 




a % values are the changes in treatment mean Cmax or AUC with respect to monotherapy



↔ = No effect on Cmax and AUC (



NS = Not studied



*DEA = des acetyl diltiazem, DEM = N-demethyl diltiazem



b Flunarizine AUC increased 14 % in subjects taking flunarizine alone. Increase in exposure may be attributed to accumulation during achievement of steady state.


  


4.6 Pregnancy And Lactation



Topiramate was teratogenic in mice, rats and rabbits. In rats, topiramate crosses the placental barrier.



There are no adequate and well-controlled studies with topiramate in pregnant women.



Pregnancy registry data suggest that there may be an association between the use of topiramate during pregnancy and congenital malformations (e.g., craniofacial defects, such as cleft lip/palate, hypospadias, and anomalies involving various body systems). This has been reported with topiramate monotherapy and topiramate as part of a polytherapy regimen. This data should be interpreted with caution, as more data is needed to identify increased risks for malformations.



In addition, data from these registries and other studies suggest that, compared with monotherapy, there may be an increased risk of teratogenic effects associated with the use of anti-epileptic drugs in combination therapy.



It is recommended that women of child bearing potential use adequate contraception.



Animal studies have shown excretion of topiramate in milk. The excretion of topiramate in human milk has not been evaluated in controlled studies. Limited observations in patients suggest an extensive excretion of topiramate into breast milk. Since many medicinal products are excreted into human milk, a decision must be made whether to suspend breast-feeding or to discontinue/ abstain from topiramate therapy taking into account the importance of the medicinal product to the mother (section 4.4).



Indication Epilepsy



During pregnancy, topiramate should be prescribed after fully informing the woman of the known risks of uncontrolled epilepsy to the pregnancy and the potential risks of the medicinal product to the foetus.



Indication Migraine Prophylaxis



Topiramate is contraindicated in pregnancy, and in women of childbearing potential if an effective method of contraception is not used (see section 4.3 and 4.5 Interactions with oral contraceptives).



4.7 Effects On Ability To Drive And Use Machines



Topiramate acts on the central nervous system and may produce drowsiness, dizziness or other related symptoms. It may also cause visual disturbances and/or blurred vision. These adverse reactions could potentially be dangerous in patients driving a vehicle or operating machinery, particularly until such time as the individual patient's experience with the medicinal products established.



No studies on the effects on the ability to drive and use machines have been performed.



4.8 Undesirable Effects



The safety of topiramate was evaluated from a clinical trial database consisting of 4,111 patients (3,182 on topiramate and 929 on placebo) who participated in 20 double-blind trials and 2,847 patients who participated in 34 open-label trials, respectively, for topiramate as adjunctive treatment of primary generalized tonic-clonic seizures, partial onset seizures, seizures associated with Lennox-Gastaut syndrome, monotherapy for newly or recently diagnosed epilepsy or migraine prophylaxis. The majority of ADRs were mild to moderate in severity. ADRs identified in clinical trials, and during post-marketing experience (as indicated by “*”) are listed by their incidence in clinical trials in Table 1. Assigned frequencies are as follows:



Very common



Common



Uncommon



Rare



Not known cannot be estimated from the available data



The most common ADRs (those with an incidence of >5 % and greater than that observed in placebo in at least 1 indication in double-blind controlled studies with topiramate) include: anorexia, decreased appetite, bradyphrenia, depression, expressive language disorder, insomnia, coordination abnormal, disturbance in attention, dizziness, dysarthria, dysgeusia, hypoesthesia, lethargy, memory impairment, nystagmus, paresthesia, somnolence, tremor, diplopia, vision blurred, diarrhoea, nausea, fatigue, irritability, and weight decreased.



Paediatric population



ADRs reported more frequently (



decreased appetite



increased appetite



acidosis hyperchloraemic



hypokalaemia



abnormal behaviour



aggression



apathy



initial insomnia



suicidal ideation



disturbance in attention



lethargy



circadian rhythm sleep disorder



poor quality sleep



lacrimation increased



sinus bradycardia



feeling abnormal



gait disturbance.



ADRs that were reported in children but not in adults in double-blind controlled studies include:



eosinophilia



psychomotor hyperactivity



vertigo



vomiting



hyperthermia



pyrexia



learning disability.









































































Table 1: Topiramate Adverse Drug Reactions


     


System Organ Class




Very common




Common




Uncommon




Rare




Not known




Investigations




Weight decreased




Weight increased*




Crystal urine present, tandem gait test abnormal, white blood cell count decreased




Blood bicarbonate decreased



 


Cardiac disorders



 

 


Bradycardia, sinus bradycardia, palpitations



 

 


Blood and lymphatic system disorders



 


Anaemia




Leucopenia, thrombocytopenia lymphadenopathy, eosinophilia




Neutropenia*



 


Nervous system disorders




Paraesthesia, somnolence



Dizziness




Disturbance in attention, memory impairment, amnesia, cognitive disorder, mental impairment, psychomotor skills impaired, convulsion, coordination abnormal, tremor, lethargy, hypoaesthesia, nystagmus, dysgeusia, balance disorder, dysarthria, intention tremor, sedation




Depressed level of consciousness, grand mal convulsion, visual field defect, complex partial seizures, speech disorder, psychomotor hyperactivity, syncope, sensory disturbance, drooling, hypersomnia, aphasia, repetitive speech, hypokinesia, dyskinesia, dizziness postural, poor quality sleep, burning sensation, sensory loss, parosmia, cerebellar syndrome, dysaesthesia, hypogeusia, stupor, clumsiness, aura, ageusia, dysgraphia, dysphasia, neuropathy peripheral, presyncope, dystonia, formication




Apraxia, circadian rhythm sleep disorder, hyperaesthesia, hyposmia, anosmia, essential tremor, akinesia, unresponsive to stimuli



 


Eye disorders



 


Vision blurred, diplopia, visual disturbance




Visual acuity reduced, scotoma, myopia*, abnormal sensation in eye*, dry eye, photophobia, blepharospasm, lacrimation increased, photopsia, mydriasis, presbyopia




Blindness unilateral, blindness transient, glaucoma, accommodation disorder, altered visual depth perception, scintillating scotoma, eyelid oedema*, night blindness, amblyopia




Angle closure glaucoma*, Maculo-pathy*, eye movement disorder*




Ear and labyrinth disorders



 


Vertigo, tinnitus, ear pain




Deafness, deafness unilateral, deafness neurosensory, ear discomfort, hearing impaired



 

 


Respiratory, thoracic and mediastinal disorders



 


Dyspnoea , epistaxis, nasal congestion, rhinorrhoea




Dyspnoea exertional, Paranasal sinus hypersecretion, dysphonia



 

 


Gastrointestinal disorders




Nausea, diarrhoea




Vomiting, constipation, abdominal pain upper, dyspepsia, abdominal pain, dry mouth, stomach discomfort, paraesthesia oral, gastritis, abdominal discomfort




Pancreatitis, flatulence, gastrooesophageal reflux disease, abdominal pain lower, hypoaesthesia oral, gingival bleeding, abdominal distension, epigastric discomfort, abdominal tenderness, salivary hypersecretion, oral pain, breath odour, glossodynia



 

 


Renal and urinary disorders



 


Nephrolithiasis, pollakiuria, dysuria




Calculus urinary, urinary incontinence, haematuria, incontinence, micturition urgency, renal colic, renal pain




Calculus ureteric, renal tubular acidosis*



 


Skin and subcutaneous tissue disorders



 


Alopecia, rash, pruritus




Anhidrosis, hypoaesthesia facial, urticaria, erythema, pruritus generalised, rash macular, skin discolouration, derma

No comments:

Post a Comment