Contraindications for Topiramate Usage
Topiramate is absolutely contraindicated in patients with a history of hypersensitivity to any component of the medication. 1
Primary Contraindications
Pregnancy and women who may become pregnant: Topiramate is teratogenic and has been associated with cleft lip/palate, making it contraindicated in women who are pregnant or may become pregnant without reliable contraception 2
Hypersensitivity reactions: Patients with known hypersensitivity to topiramate or any of its components should not use this medication 1
Medical Conditions Where Topiramate Should Be Avoided
Uncontrolled hypertension: Due to potential cardiovascular effects, especially when used in combination formulations like phentermine/topiramate ER 2
History of cardiovascular disease: The sympathomimetic effects, particularly in combination products containing phentermine, can exacerbate cardiovascular conditions 2
Untreated hyperthyroidism: Increases risk of arrhythmias and seizures 2
Concomitant use with monoamine oxidase inhibitors (MAOIs): Should not be used within 14 days of MAOI use 2
History of significant nephrolithiasis: Topiramate has carbonic anhydrase inhibitor properties that can increase risk of kidney stones 2
Special Precautions and Relative Contraindications
Seizure disorders: For combination products containing naltrexone/bupropion with topiramate 2
Perioperative period: Discontinuation recommended at least 4 days before procedures requiring general anesthesia due to potential hyperadrenergic effects and refractory hypotension 2
Metabolic acidosis risk: Caution in conditions predisposing to acidosis due to topiramate's carbonic anhydrase inhibition 3, 4
Renal impairment: As topiramate is primarily excreted renally, dosage adjustments may be needed 5
Monitoring Requirements
Pregnancy testing: Monthly pregnancy tests recommended for women of reproductive potential 2
Serum bicarbonate levels: Periodic monitoring recommended for long-term therapy due to risk of metabolic acidosis 2
Blood pressure and heart rate: Regular monitoring, especially during initial titration 2
Discontinuation Criteria
Phentermine/topiramate ER: Should be discontinued if 3% weight loss is not achieved after 12 weeks at 7.5/46 mg daily, or if 5% weight loss is not achieved after 12 weeks on the maximum dose (15/92 mg daily) 2
Worsening cognitive function: If significant cognitive impairment occurs, especially problems with expressive speech and verbal memory 6
Development of metabolic acidosis: If persistent despite intervention 4
Development of acute angle-closure glaucoma: A rare but serious adverse effect 2
The contraindications and precautions for topiramate use should be carefully evaluated before initiating therapy, with particular attention to pregnancy risk, cardiovascular status, and potential for drug interactions 2.