チオテパ
チオテパは、強力で細胞周期非特異的な**アルキル化抗悪性腫瘍薬**です。 獣医療では主に以下の目的で使用されます： * 悪性腫瘍性胸水・腹水の管理のための**体腔内注入**。 * 膀胱移行上皮癌に対する**膀胱内注入**（ただし、全身性のドキソルビシン/シクロホスファミド療法と比較して有効性が著しく低いことが研究で示されています）。 * 各種癌に対する全身性の補助療法。 > **臨床上のポイント：** チオテパの治療指数は非常に狭いです。危険な細胞毒性薬であるため、変異原性および催奇形性のリスクから獣医療従事者を保護するために、厳格な取り扱い手順（安全キャビネット、閉鎖式薬物移送システム、適切な個人用防護具の使用など）が必須です。
作用機序: Thiotepa acts as a polyfunctional alkylating agent. * **Mechanism:** It undergoes conversion to its active metabolite, **TEPA**, which directly cross-links DNA strands by binding to guanine bases. * **Pathway:** DNA cross-linking → interference with DNA replication and RNA transcription → cell cycle arrest and apoptosis. * **Specificity:** It is **cell-cycle non-specific**, meaning it exerts cytotoxic effects on both resting and actively dividing cells. * When administered via the intracavitary route, it is believed to control malignant effusions through a direct, localized antineoplastic effect on the serosal surfaces.
動物種別の用量
- Intracavitary use for neoplastic effusions or systemically for adjunctive therapy of carcinomas · 0.2-0.5 mg/m 2 · intracavitary; IV · Not specified · Not specified · Consultation with a veterinary oncologist and referral to current veterinary oncology references are strongly recommended.
用量は獣医療従事者向けの臨床リファレンスです。必ず最新の添付文書と個々の患者で確認してください。
投与経路
禁忌
- Hypersensitivity to thiotepa
- Pregnancy (teratogenic and mutagenic - FDA Category D)
有害事象
- Leukopenia (most common)
- Thrombocytopenia
- Anemia
- Pancytopenia
- Vomiting
- Diarrhea
- Stomatitis
- Intestinal ulceration
- Dizziness (reported in humans)
- Headache (reported in humans)
薬物相互作用
- Immunosuppressive drugs (e.g., azathioprine, cyclophosphamide, corticosteroids) · May increase the risk of severe infections due to additive immunosuppression.
- Myelosuppressive drugs (e.g., chloramphenicol, flucytosine, amphotericin B, colchicine) · Extreme caution required; bone marrow depression may be additive and lead to severe pancytopenia.
- Live Vaccines · Increased risk of vaccine-induced infection or reduced vaccine efficacy; use with extreme caution, if at all.
モニタリング
- Clinical efficacy (tumor response or reduction in effusion)
- CBC with platelets (monitor closely for myelosuppression)
- Serum uric acid levels
過量投与
There is **no specific antidote** for a thiotepa overdose. Treatment is primarily supportive and symptomatic. If severe hematologic toxicity (profound myelosuppression) occurs, aggressive supportive therapy is required, which may include **transfusions of appropriate blood products**, broad-spectrum prophylactic antibiotics, and isolation to prevent secondary infections.
VetSheet の薬剤リファレンスは、獣医療従事者向けの臨床意思決定支援を目的としており、専門的判断やメーカーの最新添付文書に代わるものではありません。