Hydrocortisone

Corticosteroid Glucocorticoid

Dosage & Administration Guidelines

Species Route Dose Frequency Duration & Clinical Notes
Dog PO 0.5-1 mg/kg/day for anti-inflammatory; 2-4 mg/kg/day for immunosuppressive q12h or divided q12h Duration: Varies; taper for long-term use
Notes: For Addison's disease: 0.2-0.5 mg/kg/day in divided doses. Use lowest effective dose.
Dog IV 5-15 mg/kg for shock Single dose or q6h as needed Duration: Short-term (24-48 hours)
Notes: High-dose for shock; monitor for electrolyte imbalances.
Cat PO 0.5-1 mg/kg/day for anti-inflammatory; 2-4 mg/kg/day for immunosuppressive q12h or divided q12h Duration: Varies; taper for long-term use
Notes: For Addison's disease: 0.2-0.5 mg/kg/day in divided doses. Use lowest effective dose.
Cat IV 5-10 mg/kg for shock Single dose or q6h as needed Duration: Short-term (24-48 hours)
Notes: High-dose for shock; monitor for electrolyte imbalances.
Horse IV 0.5-1 mg/kg for anti-inflammatory; 2-4 mg/kg for shock q12-24h Duration: Short-term (1-3 days)
Notes: For heaves: 0.5-1 mg/kg IV q12h for 3-5 days, then taper.
Horse IA 25-50 mg per joint Single dose Duration: As needed
Notes: Intra-articular injection for arthritis; strict aseptic technique.
Cattle IV 0.5-1 mg/kg for anti-inflammatory; 2-4 mg/kg for shock q12-24h Duration: Short-term (1-3 days)
Notes: For ketosis: 100-200 mg IV or IM once.
Cattle IM 0.5-1 mg/kg q12-24h Duration: Short-term
Notes: For ketosis: 100-200 mg IM once.
Small Ruminants IV 0.5-1 mg/kg q12-24h Duration: Short-term
Notes: For pregnancy toxemia: 1-2 mg/kg IV once, may repeat in 24h.
Rabbit PO 0.5-2 mg/kg q12-24h Duration: Short-term; taper
Notes: Use with caution; rabbits are sensitive to corticosteroids.
Bird IM 0.5-2 mg/kg q12-24h Duration: Short-term
Notes: Use with caution; immunosuppression risk.

Clinical Indications & Species Uses

General Indications
  • Anti-inflammatory and immunosuppressive therapy
  • Replacement therapy for adrenal insufficiency
  • Management of shock
  • Topical treatment for inflammatory skin and ear conditions
Dog (Canine)
  • Anti-inflammatory therapy for allergic dermatitis, arthritis, and inflammatory bowel disease
  • Immunosuppressive therapy for immune-mediated hemolytic anemia, thrombocytopenia, and lupus
  • Replacement therapy for adrenocortical insufficiency (Addison's disease)
  • Management of shock (high-dose IV)
  • Topical treatment for otitis externa and skin inflammation
Cat (Feline)
  • Anti-inflammatory therapy for allergic dermatitis, asthma, and inflammatory bowel disease
  • Immunosuppressive therapy for immune-mediated diseases
  • Replacement therapy for hypoadrenocorticism
  • Topical treatment for otitis externa and skin inflammation
Horse (Equine)
  • Anti-inflammatory therapy for arthritis, bursitis, and allergic reactions
  • Treatment of heaves (recurrent airway obstruction) as adjunctive therapy
  • Management of shock (high-dose IV)
  • Topical treatment for eye inflammation (ophthalmic preparations)
Cattle (Bovine)
  • Anti-inflammatory therapy for respiratory disease, mastitis, and arthritis
  • Treatment of ketosis (as a glucocorticoid to increase glucose production)
  • Management of shock
  • Topical treatment for skin conditions
Small Ruminants (Sheep / Goat)
  • Anti-inflammatory therapy for arthritis, pneumonia, and allergic reactions
  • Treatment of pregnancy toxemia (as a glucocorticoid to induce parturition or manage metabolic disease)
  • Management of shock
Rabbit & Small Mammals
  • Anti-inflammatory therapy for dermatitis, arthritis, and respiratory disease
  • Immunosuppressive therapy for immune-mediated diseases (use with caution)
  • Topical treatment for skin inflammation
Avian & Poultry
  • Anti-inflammatory therapy for arthritis, dermatitis, and respiratory disease
  • Management of shock (use with caution due to immunosuppression)
  • Topical treatment for skin conditions
Exotic & Other Species
  • Anti-inflammatory therapy in reptiles, small mammals, and other exotic species (doses vary widely; use with caution)
  • Replacement therapy for adrenal insufficiency in some species

Pharmacology & Mechanism of Action

Drug Class: Corticosteroid | Pharmacological Group: Glucocorticoid

Mechanism of Action: Hydrocortisone is a short-acting glucocorticoid that binds to the glucocorticoid receptor, leading to changes in gene transcription. It induces the synthesis of lipocortin, which inhibits phospholipase A2, thereby reducing the release of arachidonic acid and subsequent production of prostaglandins, leukotrienes, and other inflammatory mediators. It also suppresses the immune response by inhibiting cytokine production, reducing leukocyte migration, and decreasing capillary permeability. Additionally, it has mineralocorticoid activity, promoting sodium and water retention and potassium excretion.

Pharmacodynamics: Hydrocortisone exerts anti-inflammatory, anti-allergic, and immunosuppressive effects. It stabilizes lysosomal membranes, reduces fibroblast proliferation, and decreases collagen deposition. It also affects carbohydrate, protein, and fat metabolism, promoting gluconeogenesis and protein catabolism. Its mineralocorticoid activity is about 1/100th that of aldosterone but can be clinically significant at high doses. The onset of action is relatively rapid after IV administration, with peak effects within 1-2 hours. Duration of action is short, typically 8-12 hours.

⚡ Pharmacokinetics Summary

Absorption: Hydrocortisone is well absorbed after oral administration, with peak plasma concentrations occurring within 1-2 hours. It is also absorbed systemically after topical application, but absorption is variable depending on the site and condition of the skin. Intramuscular and subcutaneous injections provide slower absorption, with effects lasting longer than IV administration.
Distribution: Hydrocortisone is widely distributed throughout the body. It crosses the placenta and is distributed into milk. It is bound to plasma proteins, primarily corticosteroid-binding globulin (CBG) and albumin, with about 90% bound at therapeutic concentrations.
Metabolism: Hydrocortisone is metabolized primarily in the liver via reduction and conjugation to inactive metabolites. The enzyme 11β-hydroxysteroid dehydrogenase converts it to cortisone, which is inactive. Metabolism is rapid, and the half-life is short.
Excretion: Metabolites are excreted primarily in the urine as glucuronide and sulfate conjugates. A small amount is excreted in feces. The elimination half-life is approximately 1-2 hours in dogs and cats, but the biological half-life is longer (8-12 hours) due to intracellular effects.
Half-Life: Plasma half-life: 1-2 hours in dogs and cats; 1-1.5 hours in horses; 1-2 hours in cattle. Biological half-life: 8-12 hours.
Bioavailability: Oral bioavailability is high, approximately 80-100% in dogs. Topical absorption is variable, typically 1-10% depending on formulation and skin integrity.
Protein Binding: Approximately 90% bound to plasma proteins (CBG and albumin).

Available Formulations & Strengths

Oral Tablet 5 mg, 10 mg, 20 mg (PO)
Oral Solution 1 mg/mL, 2 mg/mL (PO)
Injectable Solution 50 mg/mL, 100 mg/mL (IV, IM, SC)
Topical Cream/Ointment 0.5%, 1%, 2.5% (Topical)
Ophthalmic Suspension/Ointment 0.5%, 1% (Ophthalmic)
Otic Suspension 1% (Otic)

Contraindications & Clinical Warnings

Contraindications:
  • Systemic fungal infections
  • Known hypersensitivity to hydrocortisone
  • Administration of live vaccines during immunosuppressive therapy
  • Use in animals with corneal ulcers (topical ophthalmic)
  • Use in animals with gastrointestinal ulcers or perforation
  • Use in pregnant animals unless benefits outweigh risks (may cause fetal abnormalities)
Warnings & Clinical Precautions:
  • Use with caution in animals with diabetes mellitus, renal disease, heart disease, or hypertension
  • May cause immunosuppression, increasing susceptibility to infections
  • Prolonged use may lead to iatrogenic hyperadrenocorticism (Cushing's syndrome)
  • Abrupt withdrawal after prolonged therapy may cause adrenal insufficiency; taper dose gradually
  • Use with caution in animals with osteoporosis or glaucoma
  • In food animals, observe withdrawal times; extra-label use requires veterinary oversight
  • Topical use on large areas or broken skin may cause systemic effects
  • In horses, avoid intra-articular injection if infection is suspected

Adverse Effects & Reactions

Common:

  • Increased thirst and urination (polydipsia/polyuria)
  • Increased appetite
  • Panting (in dogs)
  • Gastrointestinal upset (vomiting, diarrhea)
  • Lethargy

Serious / Severe:

  • Iatrogenic hyperadrenocorticism (Cushing's syndrome) with prolonged use
  • Adrenal suppression and insufficiency upon withdrawal
  • Gastrointestinal ulceration or perforation
  • Diabetes mellitus or worsening of existing diabetes
  • Immunosuppression leading to opportunistic infections
  • Pancreatitis
  • Hepatopathy
  • Delayed wound healing

Rare:

  • Anaphylactic reactions
  • Behavioral changes (agitation, depression)
  • Seizures
  • Cardiac arrhythmias
  • Osteoporosis or pathological fractures
  • Growth retardation in young animals

Key Drug Interactions

Interacting Drug / Class Clinical Effect & Mechanism Severity
Nonsteroidal anti-inflammatory drugs (NSAIDs) Increased risk of gastrointestinal ulceration and bleeding High
Insulin or oral hypoglycemic agents May increase blood glucose, requiring dose adjustment of antidiabetic agents Moderate
Phenobarbital or phenytoin Increased hepatic metabolism of hydrocortisone, reducing its efficacy Moderate
Potassium-depleting diuretics (e.g., furosemide, thiazides) Increased risk of hypokalemia Moderate
Amphotericin B Increased risk of hypokalemia and cardiac toxicity High
Vaccines (live) Immunosuppression may reduce vaccine efficacy and increase risk of vaccine-induced disease Moderate
Cyclosporine Additive immunosuppression; may increase risk of infection Moderate

Overdose & Toxicity Management

Signs of Toxicity:

  • Polydipsia, polyuria, polyphagia
  • Gastrointestinal ulceration or hemorrhage
  • Hyperglycemia
  • Electrolyte imbalances (hypokalemia, hypernatremia)
  • Hypertension
  • Immunosuppression
  • Behavioral changes
  • Cushing's syndrome with chronic overdose

Emergency Treatment Protocol: Treatment is primarily supportive. For acute overdose, induce vomiting if oral and within 2 hours, or perform gastric lavage. Administer activated charcoal to reduce absorption. Monitor vital signs, blood glucose, electrolytes, and fluid balance. Provide symptomatic treatment for gastrointestinal ulceration (e.g., antacids, H2 blockers, proton pump inhibitors). In cases of severe hyperglycemia, insulin may be required. For chronic overdose, gradually taper the drug to avoid adrenal insufficiency. There is no specific antidote.

Food Animal Withdrawal Times

🥩 Meat: 0 days🥛 Milk: 0 days🥚 Eggs: 0 days

Hydrocortisone is generally not approved for use in food animals in many countries. Withdrawal times may vary by country and formulation. In the US, there are no established withdrawal times for hydrocortisone in food animals; extra-label use requires a veterinary prescription and extended withdrawal periods may be recommended. Consult regulatory authorities for specific guidance.

Storage, Handling & Regulatory Information

Storage Temperature: Store at controlled room temperature 20-25°C (68-77°F), excursions permitted between 15-30°C (59-86°F).

Light Sensitivity: Light-sensitive — protect from direct exposure.

Handling & Special Conditions: Protect from light and moisture. Keep container tightly closed. Do not freeze injectable solutions. Topical preparations should be stored at room temperature and not exposed to excessive heat.

Dispensing Status: Prescription Required (Rx Only)

Approval Status: Approved for veterinary use in various formulations (e.g., topical, ophthalmic, injectable) in dogs, cats, and horses. Not approved for food animals in the US.

Extra-Label (Off-Label) Use: In the US, hydrocortisone is available by prescription. Extra-label use in food animals is permitted under AMDUCA (Animal Medicinal Drug Use Clarification Act) only with a valid veterinary-client-patient relationship, and must follow established withdrawal times. Use in non-food animals is common. In some countries, hydrocortisone may be available over-the-counter for topical use.

Clinical Pearls & Practice Notes

💡 Clinical Insights: Hydrocortisone is a short-acting corticosteroid with both glucocorticoid and mineralocorticoid activity. It is useful for acute anti-inflammatory and immunosuppressive therapy, as well as for replacement therapy in Addison's disease. Due to its mineralocorticoid effects, it may cause sodium and water retention, especially at high doses. For long-term therapy, other corticosteroids with less mineralocorticoid activity (e.g., prednisone, prednisolone) are often preferred. When using hydrocortisone, it is important to use the lowest effective dose for the shortest duration possible, and to taper the dose gradually to avoid adrenal suppression. In food animals, extra-label use requires careful consideration of withdrawal times. Topical formulations are commonly used for dermatological and otic conditions. Always monitor for adverse effects, especially with prolonged use.

References & Literature

  • 📚 Plumb's Veterinary Drug Handbook
  • 📚 Papich Veterinary Pharmacology and Therapeutics
  • 📚 Compendium of Veterinary Products (CVP)