菸鹼醯胺
Niacinamide
Nicotinamide
別名: Vitamin PP · Niacinamide · Nicotinamide · Nicotinamidum · Nicotinic acid amide · Nicotylamide · Vitamin B3 amide
由 VetSheet 獸醫團隊審訂更新於 2026年4月5日本內容以實證獸醫文獻為本
劑量為合格獸醫專業人員的臨床參考。請務必對照最新仿單及個別病患確認。
各物種劑量
🌎 NA — North America🌍 EU — Europe
狗
| 適應症 | 劑量 | 途徑 | 頻次 | 療程 | 地區 |
|---|---|---|---|---|---|
| Discoid lupus erythematosus | For dogs weighing 10 kg or more: 500 mg of niacinamide and 500 mg of tetracycline PO q8h. For dogs weighing from 5-10 kg: 250 mg of each drug PO q8h. For dogs weighing less than 5 kg: 100 mg of each drug PO q8h. | PO | q8h | Improvement usually noted within 6 weeks | 🌎 NA |
| Discoid lupus erythematosus or pemphigus | Dogs weighing more than 10 kg: 500 mg of niacinamide and 500 mg of tetracycline PO q8h. For dogs weighing less than 10 kg: 250 mg of each PO q8h. | PO | q8h | — | 🌎 NA |
| Various immune-mediated diseases (DLE, pemphigus, vasculitis, dermatomyositis, etc.) | For dogs less than 10 kg: 250 mg each of niacinamide and tetracycline PO three times daily. For dogs larger than 10 kg: 500 mg each of niacinamide and tetracycline PO three times daily. | PO | TID | — | 🌎 NA |
| Pemphigus foliaceous | Doses as above (with prednisone and azathioprine). Once remission has occurred the dose may be gradually tapered to once daily administration. | PO | TID initially, taper to q24h | Improvement within 1-2 months | 🌎 NA |
| Adjunctive therapy for pemphigus or discoid lupus erythematosus | 100 mg of each for dogs <5kg; 250 mg of each for dogs 5-10 kg; 500 mg of each for dogs >10 kg PO three times daily until resolve (90-120 days), then decrease by one dose per day per month (three times daily to two times daily to once daily and eventually to every other day for 30-60 days.) | PO | TID initially, then tapered | 90-120 days initially, then 30-60 days taper | 🌎 NA |
| Immunomodulation (e.g., lupoid onychodystrophy, discoid lupus erythematosus, pemphigus foliaceus) | 250 mg/dog (dogs up to 25 kg), 500 mg/dog (dogs >25 kg) | PO | q8h | Taper to effect | 🌍 EU |
- Discoid lupus erythematosus: Given in combination with tetracycline.
- Discoid lupus erythematosus or pemphigus: May use in combination with corticosteroids and Vitamin E. If adverse effects become a problem, reduce dose of niacinamide first.
- Various immune-mediated diseases (DLE, pemphigus, vasculitis, dermatomyositis, etc.): May substitute doxycycline for tetracycline at 5 mg/kg PO once a day.
- Pemphigus foliaceous: Used as adjunctive therapy.
- Adjunctive therapy for pemphigus or discoid lupus erythematosus: Given with tetracycline.
- Immunomodulation (e.g., lupoid onychodystrophy, discoid lupus erythematosus, pemphigus foliaceus): Often used in combination with oxytetracycline, tetracycline, or doxycycline.
劑量為合格獸醫專業人員的臨床參考。請務必對照最新仿單及個別病患確認。
概覽
菸鹼醯胺（Niacinamide，又稱 Nicotinamide）是維生素 B3 的水溶性醯胺形式。雖然它作為組織呼吸和脂質代謝的必需營養素，但在獸醫藥理學中，其主要用途是作為免疫調節劑。
在犬科醫學中，它最常與四環黴素 (Tetracycline) 或去氧羥四環素 (Doxycycline) 產生協同作用，用於控制免疫介導的皮膚疾病。它對盤狀紅斑性狼瘡 (DLE) 和紅斑性天疱瘡特別有效，在 25% 到 65% 的患犬中顯示出療效。
臨床要點： 區分菸鹼醯胺 (Niacinamide) 和菸鹼酸 (Niacin) 非常重要。與菸鹼酸不同，菸鹼醯胺不會引起皮膚血管擴張（即「菸鹼酸潮紅」），也不會影響血脂水平或心血管系統，因此是犬隻長期免疫調節的更安全選擇。
作用機轉
At pharmacologic doses, niacinamide exerts anti-inflammatory and immunomodulatory effects through several pathways:
- Mast Cell Stabilization: Blocks IgE-induced histamine release and prevents the degranulation of mast cells.
- Enzyme Inhibition: Inhibits phosphodiesterase (PDE) enzymes → increases intracellular cAMP → decreases the release of inflammatory proteases.
- Synergy with Tetracyclines: When used concurrently with tetracycline or doxycycline, the combination suppresses leukocyte chemotaxis that occurs secondary to complement activation by antibody-antigen complexes.
- Nutritional Role: Acts as a precursor to NAD and NADP, essential coenzymes for tissue respiration, glycogenolysis, and lipid metabolism.
安全性與警告
禁忌症
- Liver disease
- Active peptic ulcers
- Hypersensitivity to niacinamide
- Do not use nicotinic acid (niacin) as a substitute due to severe vasodilation (flushing) effects.
不良反應
- Lethargy
- Elevated liver enzymes (occasional)
- Increased seizure frequency (anecdotal)
- Mild gastrointestinal irritation (anorexia, vomiting, diarrhea)
注意事項
Use with caution in dogs with a history of seizures. While niacinamide alone is generally considered safe in pregnant and lactating animals, its common concurrent use with tetracycline may not be safe during pregnancy/nursing.
藥物交互作用
May require dosage adjustments after initiating niacinamide therapy due to potential alterations in glycemic control.
May require dosage adjustments after initiating niacinamide therapy.
監測
- Clinical efficacy (resolution of dermatologic lesions)
- Adverse effects (GI upset, lethargy)
- Liver enzymes (baseline and occasional monitoring suggested)
- Clinical resolution of dermatological lesions
- Gastrointestinal signs (vomiting, diarrhea, anorexia)
- Liver enzymes (if used long-term or at high doses)
藥物動力學
半衰期
吸收
Absorbed well after oral administration.
分佈
Widely distributed to body tissues.
代謝
Metabolized in the liver to several metabolites.
排除
Excreted into the urine. At physiologic doses, only a small amount is excreted unchanged, but as dosages increase, larger quantities are excreted unchanged.
過量
Acute toxicity is rare. Overdoses are unlikely to cause significant problems other than acute gastrointestinal distress (vomiting, diarrhea).
可用產品
劑型
- Tablets
- 250 mg oral tablet
人用標示
- Niacinamide (Nicotinamide) Tablets: 100 mg & 500 mg (OTC)
- Nicotinamide 50 mg tablets
- Nicotinamide 250 mg tablets
各地核准狀態
Available as general sale.
Available as general sale.
暫無法規資料: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
儲存與穩定性
Store tablets in tight containers at room temperature unless otherwise labeled. Incompatible with alkalis or strong acids.
飼主須知
- 請嚴格按照指示餵食： 此藥物通常與抗生素（如四環黴素或去氧羥四環素）一起給予，以治療免疫介導的皮膚病。
- 請保持耐心： 通常需要 6 到 8 週（有時長達 2 個月）才能看到狗狗皮膚有明顯改善。
- 注意副作用： 如果您的狗狗出現嘔吐、食慾不振或異常疲倦，請聯繫您的獸醫師。
- 切勿隨意替代： 請確保您使用的是菸鹼醯胺 (Niacinamide) 而不是菸鹼酸 (Niacin)，因為菸鹼酸會引起不適的潮紅和其他副作用。
- 當皮膚狀況好轉時，請勿突然停藥；您的獸醫師通常會提供逐漸減量的計畫。
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