What is ammonium bituminosulfonate used for?

October 6, 2025 •

5 min read

First used in the 19th century by German physician Paul Gerson Unna, ammonium bituminosulfonate, also known as Ichthammol, is a topical medication with anti-inflammatory and antiseptic properties. For decades, people have asked, 'what is ammonium bituminosulfonate used for?', and its applications span a range of dermatological conditions, including boils, abscesses, and skin irritations.

Quick Summary

Ammonium bituminosulfonate, also known as Ichthammol or black ointment, is a topical agent used to treat skin conditions like boils, abscesses, and eczema. It possesses anti-inflammatory, antimicrobial, and keratolytic properties that reduce irritation and swelling.

Key Points

Drawing Salve Action: Ammonium bituminosulfonate, commonly known as Ichthammol or black ointment, is widely used as a 'drawing salve' to facilitate the drainage of pus from boils, abscesses, and stubborn splinters.
Anti-inflammatory Effects: It possesses anti-inflammatory properties that help reduce swelling, redness, and pain associated with a variety of skin conditions, including eczema and minor irritations.
Antimicrobial Properties: The active ingredient exhibits antibacterial and antifungal activity, making it effective against common skin infections caused by organisms like Staphylococcus aureus.
Supports Wound Healing: By softening the skin and providing antiseptic benefits, it helps create an environment conducive to the healing of infected wounds and lesions.
Used for Chronic Conditions: Beyond acute infections, Ichthammol is also applied for chronic inflammatory dermatoses like eczema and psoriasis, and can be a less irritating alternative to other treatments like coal tar.
Side Effects: Common side effects include skin irritation, a characteristic sulfur-like odor, and the potential to stain clothing and other fabrics.
Versatile Formulations: It is primarily found in topical ointments, often in 10% or 20% concentrations, and can be combined with other therapeutic agents like zinc oxide.

What is Ammonium Bituminosulfonate?

Ammonium bituminosulfonate (ABS) is a dark, thick, water-soluble substance derived from sulfur-rich shale oil, which was formed from ancient marine sediments. Also known by its original brand name, Ichthyol, it is commonly found in over-the-counter (OTC) products and is frequently called 'black ointment' or 'drawing salve' due to its appearance and traditional use. Its therapeutic effects are attributed to a high content of organically bound sulfur compounds.

Key Dermatological Uses

ABS is a versatile topical agent with a range of uses based on its anti-inflammatory, antibacterial, and skin-softening properties.

Treating Boils and Abscesses

One of the most well-known uses of ammonium bituminosulfonate is for treating boils (furuncles) and abscesses. It functions as a 'drawing salve' by softening the skin and increasing permeability, which helps to promote the drainage of pus and fluid from the infection. This can accelerate the healing process for these painful, pus-filled skin lumps.

Managing Eczema and Psoriasis

As a topical anti-inflammatory agent, ABS is used to treat inflammatory skin conditions like eczema (dermatitis). Its anti-inflammatory action helps to reduce the redness, swelling, and itching associated with flare-ups. Some European dermatology guidelines recommend its use for mild atopic eczema. It has also been used for psoriasis, where its keratolytic properties help with the excessive buildup of skin cells. Some research suggests it is a less irritating alternative to coal tar for certain types of eczema.

Other Minor Skin Conditions

Beyond boils and eczema, ammonium bituminosulfonate is used for various minor skin irritations and infections, including:

Splinters or embedded objects
Insect and bee stings
Minor cuts and wounds
Acne and acne rosacea
Ingrown hairs and nails
Ear infections (in combination with glycerol)

How Ammonium Bituminosulfonate Works

Unlike modern, single-target drugs, ABS has a multifaceted mechanism of action that contributes to its broad utility.

Anti-inflammatory Effects

Ammonium bituminosulfonate inhibits the production of inflammatory mediators like prostaglandins and leukotrienes. This mechanism reduces the inflammation and swelling at the site of skin infections or irritations, which directly alleviates pain and discomfort.

Antimicrobial Activity

ABS has proven antibacterial and antifungal properties, particularly against Gram-positive bacteria like Staphylococcus aureus. This is crucial for treating common skin infections like boils and abscesses. The antifungal action also makes it useful against yeast and fungal species like Candida albicans.

Keratolytic and Skin-Softening Properties

Ammonium bituminosulfonate has a keratolytic effect, meaning it softens and thins the outer layer of the skin (the stratum corneum). Research using 3D skin models has demonstrated that ABS interacts with structural proteins like filaggrin, increasing skin permeability. This softening action is what allows the substance to act as a 'drawing salve,' facilitating the extraction of pus or foreign bodies trapped deep within the skin.

Application and Formulations

Ammonium bituminosulfonate is most commonly available as a topical ointment, typically in concentrations of 10% or 20%. It can also be found in combination products, such as those that include zinc oxide.

For treating boils and abscesses:

Clean the affected area with warm water and mild soap.
Apply a liberal amount of the ABS ointment directly to the boil or abscess.
Cover the area with a sterile bandage or gauze to protect clothing from staining and to keep the ointment in place.
Leave the dressing on for several hours or overnight before reapplying.

For other skin conditions:

Follow a similar process, applying the ointment thinly and regularly as directed by a healthcare provider.
For ear infections, a specialized preparation of glycerol and ichthammol (G&I) is used.

Comparison with Other Topical Agents

When considering topical treatments for skin conditions, it's helpful to compare ammonium bituminosulfonate with other common options, such as coal tar and corticosteroids.


Feature	Ammonium Bituminosulfonate (Ichthammol)	Coal Tar	Corticosteroids
Mechanism	Anti-inflammatory, antibacterial, keratolytic; promotes drainage.	Keratolytic and antiproliferative; suppresses DNA synthesis in skin cells.	Potent anti-inflammatory; suppresses immune response.
Primary Uses	Boils, abscesses, eczema, psoriasis, splinters, minor skin irritations.	Psoriasis, eczema, and other inflammatory dermatoses.	Atopic dermatitis, psoriasis, rashes, and inflammatory conditions.
Key Properties	Dark color, distinctive sulfur odor, not corrosive.	Distinctive odor, can be messy, some phototoxic properties.	Colorless, odorless, can cause skin thinning with long-term use.
Side Effects	Skin irritation, burning sensation, staining of skin and clothes.	Skin irritation, folliculitis, photosensitivity.	Skin atrophy, stretch marks, acne, systemic side effects with long-term use.
Noteworthy	Time-tested remedy; less irritating than coal tar for some eczema.	Can be combined with UV therapy for enhanced effect.	Highly effective for reducing inflammation; requires careful use due to side effects.

Conclusion

Ammonium bituminosulfonate, or Ichthammol, is a historic and versatile topical medication that remains relevant for treating a variety of skin conditions. Its ability to reduce inflammation, combat bacteria, and promote drainage makes it particularly effective for localized infections like boils and abscesses. While its distinct odor and staining potential are notable, it is generally well-tolerated and offers a valuable alternative to harsher or more complex treatments for common dermatological issues. Always consult a healthcare professional for guidance on its use, especially for more severe or persistent skin conditions.

Is ammonium bituminosulfonate safe?

Ammonium bituminosulfonate is generally considered safe for topical use, but like any medication, it may cause side effects, including skin irritation, itching, or a burning sensation. It is intended for external use only and should not be applied to open wounds or mucous membranes without professional advice.

Can I use ammonium bituminosulfonate on an open wound?

While some sources mention using Ichthammol for wound healing, it is not recommended for severely weeping or open wounds. It is best suited for intact skin surrounding infected areas like boils or abscesses to help facilitate drainage. Always consult a healthcare professional for guidance on treating open wounds.

Is ammonium bituminosulfonate the same as black salve?

No, ammonium bituminosulfonate (Ichthammol) is not the same as 'black salve,' which is a highly corrosive, unproven paste intended to destroy skin tissue. Ichthammol, in contrast, does not have corrosive properties and is used as a therapeutic topical agent.

How do I prevent staining from Ichthammol ointment?

Due to its dark color and oily nature, ammonium bituminosulfonate can stain clothes and bedding. To prevent this, cover the treated area with a sterile bandage, gauze, or dressing after applying the ointment.

Can ammonium bituminosulfonate be used for pets?

Yes, ammonium bituminosulfonate is used in veterinary medicine, particularly for equine care, to treat wounds, chaps, and chronic skin infections. It can help draw out infections and soothe sores in horses and other animals.

How often should I apply Ichthammol ointment?

The frequency of application depends on the specific condition being treated, but it is often applied once or twice daily. It is best to follow the instructions on the product packaging or your healthcare provider's recommendations.

How long does it take for Ichthammol to work?

For boils and abscesses, consistent application of Ichthammol ointment can lead to drainage within a few days. For chronic conditions like eczema, symptom relief may require longer-term use.

Frequently Asked Questions

Individuals with sensitive skin or allergies to sulfur compounds should exercise caution, as Ichthammol can cause irritation, redness, or allergic reactions. It is advisable to perform a patch test on a small, inconspicuous area of skin before widespread use.

Yes, ammonium bituminosulfonate has been used to treat acne due to its anti-inflammatory and antibacterial effects. It can help reduce inflammation and assist in clearing infected pores.

Ammonium bituminosulfonate, or Ichthammol, is made by distilling sulfur-rich oil shale (bituminous schists), sulfonating the resulting oil, and neutralizing it with ammonia. This process creates a complex mixture of sulfur-containing organic compounds.

Yes, ammonium bituminosulfonate is commonly available in different strengths, such as 10% and 20% ointments, with the higher concentration typically used for more stubborn or deep-seated issues.

Ichthammol ointment should be stored in a cool, dry place, typically at room temperature (15°-30° C or 59°-86° F), with the container tightly closed to prevent contamination and drying out.

It is generally recommended to avoid applying other topical medications or cosmetics to the same area when using Ichthammol. Wait at least an hour between applications to prevent interference with its effectiveness and to reduce the risk of irritation.

While Ichthammol has a long history of use, and guidelines from professional bodies like the British Association of Dermatologists mention its use for specific conditions, its regulatory status can vary by country. It is often available as an OTC product.