Topical / paste

Ichthammol

Ichthammol (ammonium bituminosulfonate) is a sulphonated shale-oil derivative used topically, often impregnated in bandages, for chronic eczema, particularly lichenified or excoriated lesions.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

Clinical monograph

How it works

It has mild antiseptic, anti-inflammatory and antipruritic properties and is mildly keratoplastic, soothing inflamed skin and reducing itch.

Prescribing in practice

Avoid use on acutely inflamed, weeping or broken skin, where it may cause irritation; it is intended for chronic, lichenified eczema.
Commonly applied under occlusive or impregnated bandages (e.g. with zinc paste) for lichenified eczema of the limbs.
It stains skin, hair and clothing brown and has a characteristic strong odour that patients should be warned about.

Monitoring

Monitor the treated skin for irritation or sensitisation and review response to treatment clinically.

Counselling the patient

Expect a strong tar-like smell and brown staining of skin and clothing.
Stop and seek advice if the skin becomes more red, sore or itchy.
Use as directed under any bandaging provided by your clinician.

Evidence & guidelines

Ichthammol is a long-established traditional topical for chronic eczema; use is supported by clinical experience rather than large trials, and clinicians should follow the SPC and current prescribing references.

Reference: Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Pathways