Topiramate

Generic name: topiramate [ toe-PYRE-a-mate ]

Brand names: Eprontia, Qudexy XR Sprinkle, Topamax, Topamax Sprinkle, Topiramate ER (Eqv-Qudexy XR), Trokendi XR, Topiragen, Topiramate ER (Eqv-Trokendi XR)

Dosage forms: Capsule, extended-release Capsule, Solution, Tablet

Drug class: Carbonic anhydrase inhibitor anticonvulsants

Route of administration: Oral

Dose: Tablets: 25 mg, 50 mg, 100 mg, 200 mg, Sprinkle capsules: 15 mg, 25 mg, Extended-release capsules: 25 mg, 50 mg, 100 mg, 150 mg, 200 mg

Mechanism of action: Topiramate works by enhancing GABA activity, inhibiting sodium channels, and antagonizing AMPA/kainate glutamate receptors, which helps in stabilizing neuronal membranes and preventing seizures. It also inhibits carbonic anhydrase, which may contribute to its effects on migraine prevention.

Drug usage cases: Topiramate is used to treat epilepsy and is indicated for partial-onset or generalized tonic-clonic seizures in adults and children. It is also used for the prevention of migraine headaches. It may be prescribed off-label for conditions such as bipolar disorder, neuropathic pain, and weight management in combination with other medications.

Drug contraindications: Contraindicated in patients with hypersensitivity to topiramate or any of its components. It should not be used in individuals with metabolic acidosis, especially in patients taking metformin, without close monitoring.

Side effects: Common side effects include fatigue, dizziness, cognitive issues (such as memory problems or difficulty concentrating), weight loss, and tingling in the extremities (paresthesia). Serious side effects may include metabolic acidosis, kidney stones, hyperammonemia, and visual disturbances (such as acute myopia or secondary angle-closure glaucoma).

Warnings: Topiramate can cause metabolic acidosis, which should be monitored, especially in patients with underlying kidney disease. It may also increase the risk of kidney stones, cognitive impairment, and mood changes, including suicidal thoughts. Sudden discontinuation of topiramate may result in increased seizure frequency, so the dose should be gradually tapered. Adequate hydration is recommended to reduce the risk of kidney stones. Patients should avoid alcohol during treatment due to potential interactions.

Use during pregnancy or breastfeeding: Topiramate is classified as a pregnancy category D drug. It may cause harm to the fetus, including an increased risk of cleft lip and palate. Women of childbearing potential should use effective contraception, and the drug should only be used during pregnancy if the benefits outweigh the risks. Topiramate is excreted in breast milk, so breastfeeding is not recommended while taking this medication due to potential adverse effects on the infant.