토피라메이트

항경련제

**토피라메이트(Topiramate)**는 주로 개와 고양이의 난치성 발작 장애에 대한 추가(보조) 요법으로 사용되는 새로운 2세대 **항경련제**입니다. * **임상적 유용성**: **부분(초점성) 발작** 및 자동증(예: 고양이의 "달리기 발작")을 관리하는 데 특히 유용합니다. * **약동학적 특징**: 개에서 반감기가 매우 짧지만(2-4시간), 뇌 수용체에 대한 친화력이 높아 빠르게 배출됨에도 불구하고 지속적인 치료 활성을 나타냅니다. * **치료에서의 역할**: 페노바르비탈, 브롬화칼륨 또는 레베티라세탐과 같은 전통적인 1차 치료법으로 발작 조절이 불충분할 때 종종 고려됩니다. * **실제적 고려사항**: 제네릭 약물을 사용할 수 있어 비용 부담을 줄이는 데 도움이 되지만, 잦은 투여 일정(개에서는 종종 하루 3회)으로 인해 보호자의 상당한 헌신이 필요합니다.

작용 기전: Topiramate has a multimodal mechanism of action that dampens excitatory pathways and enhances inhibitory neurotransmission in the central nervous system: * **Voltage-gated Sodium Channels** → Blocks repetitive action potentials in a time-dependent manner, preventing the spread of seizure activity. * **GABA Receptors** → Increases the frequency of **GABA** activation at **GABA_A receptors**, enhancing inhibitory signals in the brain. * **AMPA/Kainate Receptors** → Antagonizes these specific glutamate receptors, directly blocking excitatory neurotransmission (without affecting NMDA receptors). * **Carbonic Anhydrase** → Weakly inhibits isoenzymes **CA-II** and **CA-IV**, though this is believed to play only a minor role in its overall antiepileptic efficacy.

동물 종별 용량

Cats

Automatisms (running fits) and focal seizure activity · 12.5-25 mg PO (total dose) q8-12h · PO · q8-12h · Gradual adaptation in dosing is recommended. Inappetence is a major adverse effect with higher doses.

Dogs

Alternative second line anticonvulsant · 5-10 mg/kg PO q12h · PO · q12h
Alternative treatment for refractory generalized and focal seizures · 5-10 mg/kg PO twice daily · PO · twice daily
Seizures (Initial dose) · 2-10 mg/kg PO q12h · PO · q12h
Seizures · 5-10 mg/kg PO twice daily · PO · twice daily · Start at the lower dosage to reduce adverse effects.
Refractory epilepsy · 2.5-5 mg/kg PO three times daily · PO · three times daily · Presently, the author is using this drug at this dose, but at this stage there is not enough data to know how effective this treatment will be.

용량은 면허 수의 전문가를 위한 임상 참고 자료입니다. 항상 최신 라벨과 개별 환자에 대해 확인하십시오.

투여 경로

금기

Hypersensitivity to topiramate
Known hypersensitivity to topiramate

이상반응

GI distress (dogs)
Inappetence (dogs, cats)
Irritability (dogs)
Sedation/Lethargy (cats, dogs)
Ataxia (dogs)
Somnolence (humans)
Dizziness (humans)
Acute myopia with secondary angle closure glaucoma (rare, humans)
Calcium phosphate renal calculi (humans)
Sedation
Ataxia
Anorexia
Weight loss
Gastrointestinal upset

약물 상호작용

Amitriptyline · Topiramate may increase amitriptyline levels
Carbonic Anhydrase Inhibitors (acetazolamide, dichlorphenamide) · Concomitant use may increase the risk of renal stone formation
CNS Depressants · May exacerbate the adverse effects of topiramate · moderate
Lamotrigine · May increase topiramate levels
Phenytoin · May decrease topiramate levels; phenytoin levels may increase · moderate
Valproic Acid · May decrease topiramate and VPA levels
Phenobarbital · May increase clearance and decrease plasma concentrations of topiramate · moderate

모니터링

Seizure frequency and severity (Efficacy)
Adverse effects (GI distress, sedation, inappetence)
Seizure frequency and severity
Body weight and appetite
Renal function in compromised patients

과용량

Overdoses in humans have caused convulsions, drowsiness/lethargy, slurred speech, blurred and double vision, impaired mentation/stupor, ataxia, metabolic acidosis, hypotension, agitation, and abdominal pain. In dogs, common findings reported to the ASPCA APCC include ataxia and lethargy. **Treatment**: * Gut emptying protocols if the ingestion was recent. * Supportive therapy. * Hemodialysis is effective in enhancing the elimination of topiramate from the body.

VetSheet 약물 레퍼런스는 면허 수의 전문가를 위한 임상 의사결정 보조 도구이며, 전문적 판단이나 제조사의 최신 라벨을 대신하지 않습니다.