馬瓦考昔
馬瓦考昔 (Mavacoxib) 是一種非常獨特的超長效非類固醇消炎止痛藥 (NSAID),屬於昔布類 (coxib)。與傳統的每日給藥不同,馬瓦考昔設計為每月給藥一次,非常適合飼主難以配合每日餵藥的病患。 **臨床要點:** 由於其半衰期極長(平均 16-17 天),一旦發生不良反應,可能會在停藥後持續數週。因此,謹慎挑選適合的病患至關重要,通常保留用於慢性骨關節炎的管理,而非急性疼痛。
作用機制: Mavacoxib is a **COX-2 selective inhibitor** (coxib). * **Arachidonic Acid Cascade:** It selectively inhibits the **cyclooxygenase-2 (COX-2)** enzyme → decreases the production of pro-inflammatory prostaglandins (such as PGE2) → reduces pain, inflammation, and fever. * **COX-1 Sparing:** At therapeutic dosages, it relatively spares **COX-1**, the constitutive enzyme responsible for synthesizing prostaglandins that protect the gastric mucosa, support platelet function, and maintain normal renal blood flow. However, COX-selectivity is relative and can be lost at higher doses or in susceptible individuals.
各物種劑量
- Any · Do not use · PO · N/A · N/A · Contraindicated in cats.
- Pain and inflammation associated with degenerative joint disease in dogs aged 12 months or more in cases where continuous treatment exceeding one month is indicated · 2 mg/kg PO given immediately before or with the dog's main meal. The treatment should be repeated 14 days later; thereafter the dosing interval is one month. · PO · Day 1, Day 14, then monthly · A treatment cycle should not exceed 7 consecutive doses (6.5 months). · Care should be taken to ensure that the tablet is ingested. THIS IS not a daily NSAID.
- Pain and inflammation associated with degenerative joint disease (osteoarthritis) · 2 mg/kg · PO · q14d for 2 doses, then q1month · Maximum of 7 doses total · Should be given immediately before or with the dog's main meal. Treatment can potentially be re-started after a 1-month break from dosing.
劑量為合格獸醫專業人員的臨床參考。請務必對照最新藥品仿單及個別病患確認。
給藥途徑
禁忌症
- Dogs less than 12 months of age
- Dogs less than 5 kg body weight
- Gastrointestinal disorders including ulceration and bleeding
- Evidence of a hemorrhagic disorder
- Impaired renal or hepatic function
- Cardiac insufficiency
- Hypersensitivity to mavacoxib, sulfonamides, or excipients
- Pregnant, breeding, or lactating animals
- Dehydrated, hypovolemic, or hypotensive animals
- Dehydrated, hypovolaemic, or hypotensive patients
- Gastrointestinal disease or ulceration
- Blood clotting disorders
- Liver disease (prolongs metabolism and causes accumulation)
- Renal disease (requires careful evaluation, generally avoid)
- Pregnant or lactating animals
不良反應
- Inappetence
- Diarrhea
- Vomiting
- Depression
- Renal toxicity
- Gastrointestinal ulceration
- Gastrointestinal ulceration or bleeding
- Vomiting and diarrhoea
- Renal toxicity (especially if dehydrated or hypotensive)
- Hepatic accumulation (in poor metabolizers)
- Theoretical risk of precipitating cardiac failure
藥物相互作用
- ACE Inhibitors (e.g., enalapril, benazepril) · NSAIDs can reduce effects on blood pressure and potentially reduce renal blood flow, increasing the risk for renal injury.
- Aspirin · May increase the risk of gastrointestinal toxicity (ulceration, bleeding, vomiting, diarrhea). Long washout periods are warranted when switching.
- Corticosteroids (e.g., prednisone) · May increase the risk of gastrointestinal toxicity (ulceration, bleeding, vomiting, diarrhea). Concurrent use is contraindicated.
- Digoxin · NSAIDs may increase serum levels of digoxin.
- Fluconazole · May increase plasma levels of mavacoxib (extrapolated from celecoxib data in humans).
- Furosemide · NSAIDs may reduce saluretic and diuretic effects.
- Methotrexate · Serious toxicity has occurred when NSAIDs have been used concomitantly; use together with extreme caution.
- Nephrotoxic Drugs (e.g., aminoglycosides, amphotericin B) · May enhance the risk of nephrotoxicity development.
- Other NSAIDs · May increase the risk of gastrointestinal toxicity. Do not administer other NSAIDs within 1 month of the last administration of mavacoxib. · major
- Glucocorticoids · Increased risk of severe gastrointestinal ulceration and bleeding. · major
- Aminoglycosides · Increased risk of nephrotoxicity. · major
監測
- Baseline and periodic CBC and serum chemistry (including BUN/serum creatinine, and liver function assessment)
- Baseline history and physical
- Efficacy of therapy
- Adverse effect monitoring via client
- Baseline and periodic renal function (BUN, Creatinine, SDMA, USG)
- Baseline and periodic hepatic function (ALT, ALP, Bilirubin)
- Clinical signs of GI ulceration (vomiting, melaena, anorexia)
- Hydration status and blood pressure (especially during anaesthesia)
過量
In safety studies, repeated doses of 5 and 10 mg/kg did not demonstrate adverse events. At **15 mg/kg**, vomiting, softened/mucoid feces, and decreased renal function were noted. Doses of **25 mg/kg** caused GI ulceration, with one fatality from GI perforation and peritonitis. * **Management:** Manage as with other NSAID toxicity (emetics, activated charcoal, GI protectants, fluid diuresis). * **Important:** Because of the drug's very long duration of effect, prolonged monitoring and treatment may be required. Consulting a veterinary poison center is highly recommended.
VetSheet 藥物參考供持牌獸醫專業人員作臨床決策輔助之用,不能取代專業判斷或廠方最新藥品說明書。