Flumethasone
6alpha, 9alpha-difluoro-16alpha methylprednisolone
Also known as: Flucort · Cerson · Locacortene · Locortene · Lorinden · flumetasone · glumetasoni pivalas · NSC-107680
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 |
|---|---|---|---|---|---|
| Labeled indications (musculoskeletal conditions, dermatoses, allergic states, shock) | 0.0625-0.25 mg daily in divided doses | PO | daily in divided doses | — | 🌎 NA |
| Labeled indications | 0.0625-0.25 mg daily; may repeat | IV, IM, SC | daily | — | 🌎 NA |
| Labeled indications (joint inflammation) | 0.166-1 mg | Intra-articularly | — | — | 🌎 NA |
| Labeled indications (localized lesions) | 0.125-1 mg | Intra-lesionally | — | — | 🌎 NA |
| General anti-inflammatory/immunosuppressive | 0.06-0.25 mg once daily | IV, IM, SC, or PO | once daily | — | 🌎 NA |
- Labeled indications (musculoskeletal conditions, dermatoses, allergic states, shock): Tablets no longer marketed in the USA
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Labeled indications (acute and chronic dermatoses) | 0.03125-0.125 mg daily in divided doses | PO | daily in divided doses | — | 🌎 NA |
| Labeled indications (acute and chronic dermatoses) | 0.03125-0.125 mg. If necessary, may repeat. | IV, IM, or SC | If necessary, may repeat | — | 🌎 NA |
| General anti-inflammatory/immunosuppressive | 0.03-0.125 mg once daily | IV, IM, SC, or PO | once daily | — | 🌎 NA |
- Labeled indications (acute and chronic dermatoses): Tablets no longer marketed in the USA
Horses
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Labeled indications (musculoskeletal conditions, allergic states) | 1.25-2.5 mg daily. If necessary, the dose may be repeated. | IV, IM or intra-articular | daily | — | 🌎 NA |
| General anti-inflammatory | 1-2.5 mg/450 kg | IV or IM | — | — | 🌎 NA |
- Labeled indications (musculoskeletal conditions, allergic states): ARCI UCGFS Class 4 Drug
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Flumethasone is a highly potent, long-acting fluorinated glucocorticoid utilized in veterinary medicine for its profound anti-inflammatory and immunosuppressive properties.
Key pharmacological features include:
- High Potency: It is approximately 15 to 30 times more potent than hydrocortisone.
- Lack of Mineralocorticoid Activity: It exhibits virtually no appreciable mineralocorticoid (sodium-retaining) effects, reducing the risk of edema and hypertension compared to older steroids.
- Clinical Utility: It is highly effective for acute inflammatory reactions (e.g., insect bite hypersensitivity, vaccine reactions, shock), musculoskeletal inflammation (bursitis, myositis, osteoarthritis), and various acute or chronic dermatoses.
Clinical Pearl: The overarching goal of flumethasone therapy—as with all systemic corticosteroids—is to use as much as is required, and as little as possible, for as short an amount of time as possible to minimize the risk of iatrogenic hyperadrenocorticism (Cushing's syndrome) and adrenal axis suppression.
Mechanism of action
Flumethasone exerts its effects via classic genomic and non-genomic steroid pathways:
- Genomic Pathway: Free flumethasone crosses the cell membrane and binds to cytosolic glucocorticoid receptors (GR).
- The receptor-ligand complex translocates to the nucleus and binds to glucocorticoid response elements (GREs) on DNA.
- Transactivation: Upregulates the expression of anti-inflammatory proteins, notably lipocortin-1 (annexin A1). Lipocortin-1 inhibits phospholipase A2 → blocking the release of arachidonic acid from membrane phospholipids → profoundly decreasing the synthesis of pro-inflammatory prostaglandins and leukotrienes.
- Transrepression: Downregulates the expression of pro-inflammatory cytokines (e.g., IL-1, IL-6, TNF-alpha) by inhibiting transcription factors like NF-κB and AP-1.
- Non-genomic Pathway: Rapid physicochemical interactions with cellular membranes provide immediate effects, which is particularly beneficial in shock or acute hypersensitivity states.
Safety & warnings
Contraindications
- Last trimester of pregnancy (may induce parturition)
- Systemic fungal infections (unless used for Addison's replacement therapy)
- Idiopathic thrombocytopenia (specifically contraindicated for IM administration)
- Known hypersensitivity to the compound
- Chronic corticosteroid therapy of systemic diseases using sustained-release injectable forms
Adverse effects
- Polydipsia (PD), polyuria (PU), and polyphagia (PP)
- Weight gain and lipidemias
- Dull, dry haircoat and dermatological thinning
- Panting
- Gastrointestinal effects: vomiting, diarrhea, GI ulceration
- Hepatopathy: elevated liver enzymes (ALP, ALT)
- Pancreatitis
- Endocrine: activation or worsening of diabetes mellitus, iatrogenic hyperadrenocorticism (Cushingoid effects) with sustained use
- Musculoskeletal: muscle wasting, retarded growth in young animals
- Behavioral changes: depression, lethargy, viciousness
- Immunosuppression: increased susceptibility to infections
Precautions
Tapering Required: Animals that have received systemic glucocorticoids (other than short 'burst' therapy) must be tapered off slowly to allow endogenous ACTH and corticosteroid function to recover.
Stress Dosing: If an animal undergoes a 'stressor' (e.g., surgery, trauma, illness) during the tapering process or before normal adrenal/pituitary function resumes, additional glucocorticoids should be administered.
Pregnancy Warning: Corticosteroid therapy may induce parturition in large animal species during the latter stages of pregnancy. Categorized as Class C for canine and feline pregnancy (use cautiously as a last resort when benefits clearly outweigh risks).
Drug interactions
Administered concomitantly with glucocorticoids may cause hypokalemia
In patients with myasthenia gravis, concomitant administration may lead to profound muscle weakness. Discontinue anticholinesterase at least 24 hours prior if possible.
Glucocorticoids may reduce salicylate blood levels
May increase the metabolism of glucocorticoids and decrease flumethasone blood levels
Glucocorticoids may inhibit the hepatic metabolism of cyclophosphamide; dosage adjustments may be required
Concomitant administration may increase the blood levels of each by mutually inhibiting hepatic metabolism
Flumethasone may decrease diazepam levels
Administered concomitantly with glucocorticoids may cause hypokalemia
May reduce flumethasone blood levels
Insulin requirements may increase in patients receiving glucocorticoids
May decrease the metabolism of glucocorticoids and increase flumethasone blood levels; ketoconazole may induce adrenal insufficiency when glucocorticoids are withdrawn
May decrease the metabolism of glucocorticoids and increase flumethasone blood levels
May alter the metabolism of steroids; higher than usual doses of steroids may be necessary to treat mitotane-induced adrenal insufficiency
Administration of ulcerogenic drugs with glucocorticoids may increase the risk of gastrointestinal ulceration
May increase the metabolism of glucocorticoids and decrease flumethasone blood levels
May increase the metabolism of glucocorticoids and decrease flumethasone blood levels
Patients receiving immunosuppressive dosages should not receive live attenuated-virus vaccines (augmented virus replication); diminished immune response may occur with any vaccine
Monitoring
- Weight, appetite, and 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 (to assess adrenal axis suppression)
Overdose
Short-term administration of massive dosages of glucocorticoids is unlikely to cause harmful effects. There is one reported incidence of a dog developing acute CNS effects after accidental ingestion. If acute clinical signs occur, provide supportive treatment as required.
Chronic overdosage or sustained high-dose usage leads to serious adverse effects, primarily manifesting as iatrogenic hyperadrenocorticism (Cushing's syndrome), characterized by severe polyuria/polydipsia, muscle wasting, alopecia, pot-bellied appearance, and immunosuppression.
Available products
Formulations
- Injection: 0.5 mg/mL solution
- Tablets (Note: Oral formulations are generally no longer marketed in the USA)
Veterinary
- Flumethasone Injection: 0.5 mg/mL in 100 mL vials; Flucort Solution (Pfizer); (Rx)
Regulatory status
No regulatory data for: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Flumethasone injection should be stored at room temperature; avoid freezing.
Client information
Flumethasone is a potent steroid medication used to rapidly reduce inflammation, treat severe allergies, or manage certain skin and joint conditions.
- Follow Instructions Carefully: Give the exact dose prescribed. Do not stop this medication abruptly without consulting your veterinarian, as sudden withdrawal can cause a life-threatening crisis due to the body's temporary inability to produce its own natural steroids.
- Expected Side Effects: You may notice your pet drinking more water, urinating more frequently, and having an increased appetite. Panting is also common in dogs.
- When to Call the Vet: Contact your veterinarian if side effects become severe, if your pet develops vomiting, diarrhea, dark/tarry stools (a sign of stomach ulcers), extreme lethargy, or behavioral changes (like unusual aggression or depression).
- Immune System: Because this drug suppresses the immune system, keep your pet away from sick animals and consult your vet before any vaccinations.
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.