Below are the general guidelines for dosing Topamax. Note that these dosages may be adjusted on a case-by-case basis for individual patients. Always follow your prescribing physician’s instructions for taking Topamax.
The following information comes from DailyMed, an FDA label information provider.
What if I miss a dose of Topamax?
According to Mayo Clinic, if you miss a dose of Topamax, take the missed dose immediately unless you are closer in time to your next available dose. Never double doses. Further, if your next available dose is is within six hours, wait until that dose and skip the missed dose. If you miss more than one dose, contact your prescribing physician.
What if I overdose on Topamax?
**If you believe you or someone you know has overdosed, call 911 immediately for medical assistance.
Overdoses of TOPAMAX® have been reported. Signs and symptoms included convulsions, drowsiness, speech disturbance, blurred vision, diplopia, mentation impaired, lethargy, abnormal coordination, stupor, hypotension, abdominal pain, agitation, dizziness and depression. The clinical consequences were not severe in most cases, but deaths have been reported after poly-drug overdoses involving TOPAMAX®.
Topiramate overdose has resulted in severe metabolic acidosis [see WARNINGS AND PRECAUTIONS (5.3)].
A patient who ingested a dose between 96 and 110 g topiramate was admitted to a hospital with a coma lasting 20 to 24 hours followed by full recovery after 3 to 4 days.
In acute TOPAMAX® overdose, if the ingestion is recent, the stomach should be emptied immediately by lavage or by induction of emesis. Activated charcoal has been shown to adsorb topiramate in vitro. Treatment should be appropriately supportive. Hemodialysis is an effective means of removing topiramate from the body.
Dosage and Administration
It is not necessary to monitor topiramate plasma concentrations to optimize TOPAMAX® (topiramate) therapy.
On occasion, the addition of TOPAMAX® to phenytoin may require an adjustment of the dose of phenytoin to achieve optimal clinical outcome. Addition or withdrawal of phenytoin and/or carbamazepine during adjunctive therapy with TOPAMAX® may require adjustment of the dose of TOPAMAX®.
Because of the bitter taste, tablets should not be broken.
TOPAMAX® can be taken without regard to meals.
Adults and Pediatric Patients 10 Years and Older
The recommended dose for TOPAMAX® monotherapy in adults and pediatric patients 10 years of age and older is 400 mg/day in two divided doses. Approximately 58% of patients randomized to 400 mg/day achieved this maximal dose in the monotherapy controlled trial; the mean dose achieved in the trial was 275 mg/day. The dose should be achieved by titration according to the following schedule (Table 1):
|Morning Dose||Evening Dose|
|Week 1||25 mg||25 mg|
|Week 2||50 mg||50 mg|
|Week 3||75 mg||75 mg|
|Week 4||100 mg||100 mg|
|Week 5||150 mg||150 mg|
|Week 6||200 mg||200 mg|
Children Ages 2 to <10 Years
Dosing of topiramate as initial monotherapy in children 2 to < 10 years of age with partial onset or primary generalized tonic-clonic seizures was based on a pharmacometric bridging approach [see CLINICAL STUDIES (14.1)].
Dosing in patients 2 to <10 years is based on weight. During the titration period, the initial dose of TOPAMAX® should be 25 mg/day administered nightly for the first week. Based upon tolerability, the dosage can be increased to 50 mg/day (25 mg twice daily) in the second week. Dosage can be increased by 25–50 mg/day each subsequent week as tolerated. Titration to the minimum maintenance dose should be attempted over 5–7 weeks of the total titration period. Based upon tolerability and seizure control, additional titration to a higher dose (up to the maximum maintenance dose) can be attempted at 25–50 mg/day weekly increments. The total daily dose should not exceed the maximum maintenance dose for each range of body weight (Table 2).
|Weight (kg)||Total Daily Dose (mg/day)* Possible Maintenance Dose||Total Daily Dose (mg/day)* Maximum Maintenance Dose|
|Up to 11||150||250|
|12 – 22||200||300|
|23 – 31||200||350|
|32 – 38||250||350|
|Greater than 38||250||400|
|*Administered in two equally divided doses|
Adjunctive Therapy Use
Adults 17 Years of Age and Over – Partial Onset Seizures, Primary Generalized Tonic-Clonic Seizures, or Lennox-Gastaut Syndrome
The recommended total daily dose of TOPAMAX® as adjunctive therapy in adults with partial onset seizures is 200 to 400 mg/day in two divided doses, and 400 mg/day in two divided doses as adjunctive treatment in adults with primary generalized tonic-clonic seizures. It is recommended that therapy be initiated at 25 to 50 mg/day followed by titration to an effective dose in increments of 25 to 50 mg/day every week. Titrating in increments of 25 mg/day every week may delay the time to reach an effective dose. Doses above 400 mg/day (600, 800 or 1,000 mg/day) have not been shown to improve responses in dose-response studies in adults with partial onset seizures. Daily doses above 1,600 mg have not been studied.
In the study of primary generalized tonic-clonic seizures, the initial titration rate was slower than in previous studies; the assigned dose was reached at the end of 8 weeks [see CLINICAL STUDIES (14.1)].
Pediatric Patients Ages 2 – 16 Years – Partial Onset Seizures, Primary Generalized Tonic-Clonic Seizures, or Lennox-Gastaut Syndrome
The recommended total daily dose of TOPAMAX® as adjunctive therapy for pediatric patients with partial onset seizures, primary generalized tonic-clonic seizures, or seizures associated with Lennox-Gastaut syndrome is approximately 5 to 9 mg/kg/day in two divided doses. Titration should begin at 25 mg/day (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. Dose titration should be guided by clinical outcome.
In the study of primary generalized tonic-clonic seizures, the initial titration rate was slower than in previous studies; the assigned dose of 6 mg/kg/day was reached at the end of 8 weeks [see CLINICAL STUDIES (14.1)].
The recommended total daily dose of TOPAMAX® as treatment for adults for prophylaxis of migraine headache is 100 mg/day administered in two divided doses (Table 3). The recommended titration rate for topiramate for migraine prophylaxis to 100 mg/day is:
|Morning Dose||Evening Dose|
|Week 1||None||25 mg|
|Week 2||25 mg||25 mg|
|Week 3||25 mg||50 mg|
|Week 4||50 mg||50 mg|
Dose and titration rate should be guided by clinical outcome. If required, longer intervals between dose adjustments can be used.
TOPAMAX® can be taken without regard to meals.
2.3 Administration of TOPAMAX® Sprinkle Capsules
TOPAMAX® (topiramate capsules) Sprinkle Capsules may be swallowed whole or may be administered by carefully opening the capsule and sprinkling the entire contents on a small amount (teaspoon) of soft food. This drug/food mixture should be swallowed immediately and not chewed. It should not be stored for future use.
2.4 Patients with Renal Impairment
In renally impaired subjects (creatinine clearance less than 70 mL/min/1.73 m2), one-half of the usual adult dose is recommended. Such patients will require a longer time to reach steady-state at each dose.
2.5 Geriatric Patients (Ages 65 Years and Over)
Dosage adjustment may be indicated in the elderly patient when impaired renal function (creatinine clearance rate <70 mL/min/1.73 m2) is evident [see CLINICAL PHARMACOLOGY (12.3)].
2.6 Patients Undergoing Hemodialysis
Topiramate is cleared by hemodialysis at a rate that is 4 to 6 times greater than a normal individual. Accordingly, a prolonged period of dialysis may cause topiramate concentration to fall below that required to maintain an anti-seizure effect. To avoid rapid drops in topiramate plasma concentration during hemodialysis, a supplemental dose of topiramate may be required. The actual adjustment should take into account 1) the duration of dialysis period, 2) the clearance rate of the dialysis system being used, and 3) the effective renal clearance of topiramate in the patient being dialyzed.
2.7 Patients with Hepatic Disease
In hepatically impaired patients, topiramate plasma concentrations may be increased. The mechanism is not well understood.
How is Topamax supplied?
TOPAMAX® (topiramate) Tablets are available as debossed, coated, round tablets in the following strengths and colors:
25 mg cream tablet (debossed “OMN” on one side; “25” on the other) and are available in
|Bottles of 30||NDC 54868-4672-1|
|Bottles of 60||NDC 54868-4672-0|
|Bottles of 90||NDC 54868-4672-3|
50 mg light yellow tablet (debossed “OMN” on one side; “50” on the other) and are available in
|Bottles of 30||NDC 54868-5343-1|
|Bottles of 60||NDC 54868-5343-0|
100 mg yellow tablet (debossed “OMN” on one side; “100” on the other) and are available in
|Bottles of 10||NDC 54868-4674-0|
|Bottles of 30||NDC 54868-4674-1|
|Bottles of 60||NDC 54868-4674-2|
200 mg salmon tablet (debossed “OMN” on one side; “200” on the other) and are available in
|Bottles of 30||NDC 54868-5190-1|
Storage and Handling
TOPAMAX® Tablets should be stored in tightly-closed containers at controlled room temperature (59° to 86°F, 15° to 30°C). Protect from moisture.
TOPAMAX® Sprinkle Capsules should be stored in tightly-closed containers at or below 25°C (77°F). Protect from moisture.