What is Hydrocortisone-17-Butyrate?
Hydrocortisone-17-Butyrate (INCI: Hydrocortisone Butyrate; brand name: Locoid) is a butyrate ester of hydrocortisone formed by esterification at the C-17 position. Despite sharing the "hydrocortisone" name with plain hydrocortisone (Group A), the butyrate esterification fundamentally changes its chemical character — placing it in Group B (acetonide and butyrate class) of the corticosteroid contact allergen classification.
This classification distinction matters greatly clinically: a patient with Group A allergy (to plain hydrocortisone) can usually tolerate hydrocortisone-17-butyrate, and vice versa. The cross-reaction pattern is within classes, not between them.
In the context of patch testing, hydrocortisone-17-butyrate is used alongside budesonide to more completely screen for Group B steroid allergy. Its inclusion in the patch test panel increases detection sensitivity for the Group B class.
Why does Hydrocortisone-17-Butyrate cause reactions?
The mechanism is the same as for other corticosteroid contact allergens: modified Type IV delayed hypersensitivity where the molecule or its metabolites form hapten-protein conjugates. The steroid's anti-inflammatory properties partially mask the allergic reaction, leading to the characteristic pattern of incomplete treatment response.
Hydrocortisone-17-butyrate allergy is more likely in patients who:
- Have used moderately or highly potent topical steroids for extended periods
- Have chronic, treatment-resistant eczema (raising suspicion that steroid allergy is maintaining the condition)
- Have concurrent reactions to budesonide on patch testing (co-sensitization within Group B is common)
Where is Hydrocortisone-17-Butyrate found in products?
- Locoid cream and ointment: The primary product form, used for eczema, psoriasis, and contact dermatitis
- Generic hydrocortisone butyrate formulations: Available by prescription in some markets
In India, Locoid cream may be available through import or prescription channels; generic hydrocortisone butyrate preparations may also be compounded at dermatology clinics.
How to spot Hydrocortisone-17-Butyrate on labels
On pharmaceutical labels:
- Hydrocortisone Butyrate — the generic INN
- Hydrocortisone 17-Butyrate — full chemical descriptor
- Locoid — brand name
In Indian products 🇮🇳
Hydrocortisone butyrate is less commonly used in India compared to other moderately potent steroids like betamethasone valerate or mometasone furoate, which dominate the Indian prescription market. However, dermatologists managing steroid-resistant eczema may encounter it, and its inclusion in corticosteroid allergy patch test panels is important for comprehensive evaluation of Indian patients with suspected steroid contact allergy.
Given the enormous prevalence of prolonged topical steroid use in India — including inappropriate self-medication with potent steroids — corticosteroid contact allergy as a complication is likely underdiagnosed in Indian clinical settings.
Safer alternatives
- Calcineurin inhibitors: Tacrolimus and pimecrolimus for eczema management without corticosteroid contact allergy risk
- Crisaborole (Eucrisa): Phosphodiesterase-4 inhibitor for mild-moderate eczema; non-steroidal
- Dupilumab (Dupixent): Injectable biologic for moderate-severe eczema; no topical allergen concerns
- Confirmed-safe steroid class: If only Group B allergy, Group A steroids (hydrocortisone, prednisolone) may be used — but must confirm with patch testing first