Triamcinolone Acetonide
Triamcinolone acetonide
Also known as: Vetalog · Kenalog · Aristospan · triamcinoloni acetonidum · TMC
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
🌎 NA — North America🌍 EU — Europe
Dogs
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Glucocorticoid effects | 2 mg PO once daily for 7 days; 0.11-0.22 mg/kg IM or SC | PO/IM/SC | once daily (PO) or single dose (IM/SC) | 7 days for PO | 🌎 NA |
| Antiinflammatory effects | 0.05 mg/kg PO two to three times daily | PO | q8-12h | — | 🌎 NA |
| General therapy (Tablets) | 0.11 mg/kg PO initially once a day, may increase to 0.22 mg/kg PO once daily if initial response is unsatisfactory. As soon as possible, but not later than 2 weeks, reduce dose gradually to 0.028-0.055 mg/kg/day. | PO | q24h | Taper within 2 weeks | 🌎 NA |
| Inflammatory, allergic, or dermatological disorders (Injectable) | 0.11-0.22 mg/kg for inflammatory or allergic disorders, and 0.22 mg/kg for dermatological disorders. | IM/SC | As needed | Effects generally persist for 7-15 days | 🌎 NA |
| Intralesional injection | Usual dose is 1.2-1.8 mg; inject around lesion at 0.5-2.5 cm intervals. Do not exceed 0.6 mg at any one site or 6 mg total dose. | Intralesional | As needed | — | 🌎 NA |
| To prevent re-stricture after esophageal dilation | Using an endoscopically directed needle, inject 0.5-1 mL of Vetalog (2 mg/mL) submucosally at time of dilation procedure. Infiltration is done circumferentially at four points around the site. | Submucosal | Once at time of procedure | — | 🌎 NA |
- Inflammatory, allergic, or dermatological disorders (Injectable): If symptoms recur, may repeat or institute oral therapy.
- Intralesional injection: May repeat as necessary.
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Glucocorticoid effects | 0.25-0.5 mg PO once daily for 7 days | PO | q24h | 7 days | 🌎 NA |
| Pododermatitis, feline plasmacytic pharyngitis | 2-4 mg (total dose) PO once a day or every other day 0.4-0.6 mg/kg PO once daily, then taper. | PO | q24h or q48h | Tapered | 🌎 NA |
| Pemphigus complex | 0.4-0.8 mg/kg/day PO | PO | q24h | — | 🌎 NA |
| General therapy (Tablets) | 0.11 mg/kg PO initially once a day, may increase to 0.22 mg/kg PO once daily if initial response is unsatisfactory. As soon as possible, but not later than 2 weeks, reduce dose gradually to 0.028-0.055 mg/kg/day | PO | q24h | Taper within 2 weeks | 🌎 NA |
| Inflammatory, allergic, or dermatological disorders (Injectable) | 0.11-0.22 mg/kg for inflammatory or allergic disorders, and 0.22 mg/kg for dermatological disorders. | IM/SC | As needed | Effects generally persist for 7-15 days | 🌎 NA |
| Intralesional injection | Usual dose is 1.2-1.8 mg; inject around lesion at 0.5-2.5 cm intervals. Do not exceed 0.6 mg at any one site or 6 mg total dose. | Intralesional | As needed | — | 🌎 NA |
| To prevent re-stricture after esophageal dilation | Using an endoscopically directed needle, inject 0.5-1 mL of Vetalog (2 mg/mL) submucosally at time of dilation procedure. Infiltration is done circumferentially at four points around the site. | Submucosal | Once at time of procedure | — | 🌎 NA |
| Adjunctive treatment of miliary dermatitis | 0.2-0.6 mg/kg PO once daily for 10-14 days, then tapered. | PO | q24h | 10-14 days, then taper | 🌎 NA |
- Inflammatory, allergic, or dermatological disorders (Injectable): If symptoms recur, may repeat or institute oral therapy.
- Intralesional injection: May repeat as necessary.
Horses
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Glucocorticoid effects | 0.011-0.022 mg/kg PO twice daily; 0.011-0.022 mg/kg IM or SC; 6-18 mg intra-articularly or intrasynovially, may repeat after 3-4 days | PO/IM/SC/IA | q12h (PO) or as directed | — | 🌎 NA |
| Intra-articular injection | 12 mg IA on days 0, 13, 27 | IA | Specific days | 27 days | 🌎 NA |
- Glucocorticoid effects: ARCI UCGFS Class 4 Drug
Cattle
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Glucocorticoid effects | 0.02-0.04 mg/kg IM; 6-18 mg intra-articularly. | IM/IA | As directed | — | 🌎 NA |
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Triamcinolone acetonide is a synthetic, intermediate-acting glucocorticoid that is approximately 4 to 10 times (and up to 40 times in some models) more potent than hydrocortisone.
Clinical Pearls & Key Features:
- Zero Mineralocorticoid Activity: Unlike hydrocortisone or prednisone, triamcinolone lacks appreciable mineralocorticoid effects, meaning it does not cause significant sodium or water retention.
- Versatile Administration: It is utilized systemically (oral, injectable), topically, intra-articularly (especially in equine sports medicine), and intralesionally (e.g., for esophageal strictures or lick granulomas).
- Duration of Action: When given orally, its metabolic activity lasts 24-48 hours. However, intramuscular (IM) or subcutaneous (SC) depot injections can persist for 4 to 6 weeks (sometimes up to 8 weeks), making it useful for chronic inflammatory or allergic conditions where daily pilling is difficult, though this increases the risk of prolonged adrenal suppression.
- Equine Use: Frequently used for intra-articular injections in high-motion joints to reduce synovitis and improve lameness. It is an ARCI Class 4 drug in racing.
Mechanism of action
Triamcinolone exerts its effects via classic genomic and non-genomic glucocorticoid pathways:
- Genomic Pathway: Free triamcinolone crosses the cell membrane and binds to the cytosolic glucocorticoid receptor (GR).
- The receptor-ligand complex translocates to the nucleus and binds to Glucocorticoid Response Elements (GREs) on DNA.
- Anti-inflammatory Protein Induction: It upregulates the expression of lipocortin-1 (annexin A1). Lipocortin-1 inhibits phospholipase A2, thereby blocking the release of arachidonic acid from membrane phospholipids.
- Eicosanoid Suppression: This → halts the synthesis of pro-inflammatory prostaglandins and leukotrienes (via COX and LOX pathways).
- Cytokine Inhibition: It suppresses the transcription of major inflammatory cytokines (e.g., IL-1, IL-6, TNF-α) and reduces inflammatory cell migration and capillary permeability.
Safety & warnings
Contraindications
- Systemic fungal infections
- Viral infections
- Active tuberculosis
- Peptic ulcers
- Corneal ulcers
- Acute psychoses
- Cushingoid syndrome
- Idiopathic thrombocytopenia (IM administration)
- Hypersensitivity to the drug
Adverse effects
- Polyuria (PU)
- Polydipsia (PD)
- Polyphagia (PP)
- Weight gain
- Panting (dogs)
- Dull, dry haircoat
- Vomiting and diarrhea
- Elevated liver enzymes (e.g., ALP)
- Pancreatitis
- Gastrointestinal ulceration
- Lipidemias
- Insulin resistance / Activation of diabetes mellitus
- Muscle wasting
- Behavioral changes (depression, lethargy, viciousness)
- Iatrogenic hyperadrenocorticism (Cushing's syndrome) with chronic use
- Laminitis (horses)
Precautions
Tapering Required: Animals receiving systemic glucocorticoids (other than short 'burst' therapy) must be tapered off slowly to allow endogenous ACTH and adrenal function to recover.
- Stress Dosing: If a patient undergoes a stressor (surgery, trauma, illness) during tapering, additional glucocorticoids should be administered.
- Pregnancy Warning: Corticosteroid therapy may induce parturition in large animal species during the latter stages of pregnancy. Teratogenic effects are possible with excessive doses early in pregnancy (FDA Category C).
- Growth Retardation: Can retard growth when administered to young, growing animals.
- Disease Exacerbation: Use with extreme caution in patients with diabetes mellitus, osteoporosis, predisposition to thrombophlebitis, hypertension, congestive heart failure (CHF), and renal insufficiency.
Drug interactions
May cause hypokalemia when administered concomitantly
Combination in epidurals has caused serious CNS injuries and death; restrict volume to very small intrathecal test doses
May lead to profound muscle weakness in myasthenia gravis patients; discontinue 24h prior if possible
Glucocorticoids may reduce salicylate blood levels
May increase the metabolism of glucocorticoids and decrease blood levels
Glucocorticoids may inhibit hepatic metabolism of cyclophosphamide; dosage adjustments may be required
May mutually inhibit hepatic metabolism, increasing blood levels of both drugs
May cause hypokalemia
May increase triamcinolone levels
May potentiate the effects of triamcinolone
Insulin requirements may increase due to glucocorticoid-induced insulin resistance
Triamcinolone may decrease isoniazid levels
May decrease metabolism of glucocorticoids; ketoconazole may induce adrenal insufficiency upon steroid withdrawal
Higher than usual doses of steroids may be necessary to treat mitotane-induced adrenal insufficiency
Increased risk of gastrointestinal ulceration
May increase the metabolism of glucocorticoids and decrease triamcinolone blood levels
May increase the metabolism of glucocorticoids and decrease triamcinolone blood levels
May augment viral replication of live vaccines; diminished immune response to killed vaccines/toxoids
May affect INR; requires monitoring
Monitoring
- Weight, appetite, signs of edema
- Serum and/or urine electrolytes
- Total plasma proteins, albumin
- Blood glucose
- Growth and development in young animals
- ACTH stimulation test if necessary
Pharmacokinetics
Metabolism
Hepatic metabolism
Overdose
Short-term administration of massive doses is unlikely to cause harmful effects, though one case of acute CNS effects in a dog after accidental ingestion has been reported. If acute clinical signs occur, provide supportive treatment.
Chronic Toxicity: Chronic overdosage or prolonged use leads to serious adverse effects, primarily manifesting as iatrogenic hyperadrenocorticism (Cushing's syndrome), immunosuppression, and adrenal axis suppression.
Available products
Formulations
- Tablets
- Injection (suspension)
- Topical preparations
- Oral mucosal paste
- Inhaled products
Veterinary
- Triamcinolone Acetonide Tablets: 0.5 mg, 1.5 mg (Vetalog)
- Triamcinolone acetonide Suspension for Injection: 2 mg/mL; 6 mg/mL (Vetalog Parenteral)
Human-labeled
- Triamcinolone Acetonide Injection: 10 mg/mL & 40 mg/mL suspension (Kenalog-10 & -40)
- Triamcinolone Hexacetonide Injection: 5 mg/mL & 20 mg/mL suspension (Aristospan Intralesional & Intra-articular)
Regulatory status
No regulatory data for: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store at room temperature (15-30°C); the injection should be protected from light.
Client information
Important Guidance for Pet Owners:
- Expected Side Effects: It is very common for your pet to drink more water, urinate more frequently, and have an increased appetite while on this medication. Ensure they always have access to fresh water and frequent bathroom breaks.
- Do Not Stop Abruptly: If your pet has been on this medication for more than a few days, never stop it suddenly. The body's natural steroid production goes to sleep while on this drug, and stopping abruptly can cause a life-threatening crisis. Always follow your veterinarian's tapering schedule.
- Behavioral Changes: Some pets may pant more than usual, seem restless, or show changes in behavior (lethargy or irritability). Contact your vet if these are severe.
- GI Upset: Watch for vomiting, diarrhea, or dark/tarry stools, which could indicate a stomach ulcer.
- Infection Risk: Because this drug suppresses the immune system, monitor your pet for any signs of infection (e.g., skin sores that won't heal, fever) and avoid exposing them to sick animals.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.