Does Erythromycin Treat Styes? Understanding This Ophthalmic Medication

October 9, 2025 •

4 min read

Styes are a common eye condition, with some surveys indicating that approximately 1 in 5 people will experience one in their lifetime. This article explores a common question: Does erythromycin treat styes by addressing the bacterial infection that causes them?

Quick Summary

Erythromycin ophthalmic ointment is a frequently prescribed antibiotic used to treat bacterial eye infections, including styes. It works by stopping bacterial growth, promoting healing, and reducing discomfort.

Key Points

Effective Antibiotic: Erythromycin is a prescription antibiotic that effectively treats styes by stopping the growth of bacteria causing the infection.
Topical Application: It is typically applied as an ophthalmic ointment directly to the affected eyelid, targeting the infection at its source.
Combined Therapy: Treatment is most effective when the ointment is used alongside warm compresses, which help promote drainage and healing.
Proper Hygiene is Crucial: Preventing styes involves good hygiene, such as washing hands before touching eyes and properly cleaning contact lenses.
Home Care First: Most styes can be managed at home with warm compresses, but prescription medication is needed if the infection persists.
Don't Pop Styes: Squeezing a stye can worsen the infection and cause it to spread; let it drain on its own.
Know When to See a Doctor: Seek medical attention if a stye doesn't improve within a week, worsens, or affects your vision.

Understanding Styes and Their Causes

A stye, medically known as a hordeolum, is a painful, red lump that forms on the edge of an eyelid, often resembling a pimple or boil. These common afflictions are typically caused by a bacterial infection, most often from staphylococcus bacteria, in an oil gland or eyelash follicle. There are two main types of styes:

External Hordeolum: This is the more common type, forming on the outer part of the upper or lower eyelid. It's usually caused by an infection in an eyelash follicle.
Internal Hordeolum: This type forms on the inner surface of the eyelid and results from an infection in one of the oil-producing glands within the eyelid.

Certain factors can increase your risk of developing a stye. These include touching your eyes with unwashed hands, using old or contaminated cosmetics, leaving eye makeup on overnight, having chronic conditions like blepharitis (eyelid inflammation) or rosacea, and wearing contact lenses without proper hygiene.

The Role of Erythromycin in Treating Styes

Erythromycin is a macrolide antibiotic that is effective against a wide range of bacteria, including the staphylococcus bacteria that commonly cause styes. When used as a topical ophthalmic ointment, erythromycin works by inhibiting bacterial protein synthesis, which stops the bacteria from growing and reproducing. This targeted application delivers the medication directly to the site of the infection, helping to reduce inflammation, alleviate discomfort, and promote healing.

Healthcare providers frequently prescribe erythromycin ophthalmic ointment for styes. While there is a lack of large-scale clinical trials specifically on styes, its use is supported by clinical practice guidelines and its FDA-approval for superficial bacterial eye infections. It is considered an excellent choice for the types of bacteria usually responsible for styes.

How to Properly Apply Erythromycin Ointment

Correct application is crucial for the medication to be effective. Always follow your doctor's instructions.

Wash Hands: Thoroughly wash your hands with soap and water before touching your eye or the medication tube.
Prepare the Eye: Gently pull down the lower eyelid to create a small pocket.
Apply Ointment: Squeeze a small amount of ointment into the pocket without letting the tube tip touch your eye, eyelid, or any other surface.
Close Eye: Gently close your eye for a short period to allow the ointment to spread and be absorbed. Your vision may be temporarily blurry.
Clean Up: Wipe any excess ointment from the eyelid with a clean tissue and securely replace the cap on the tube.

During treatment, it's advised to avoid wearing contact lenses and eye makeup. Combining the antibiotic treatment with warm compresses applied for 10-15 minutes several times a day can help speed up the healing process by promoting drainage.

Comparing Treatment Options for Styes

While erythromycin is a common prescription, other options exist for managing styes, ranging from home remedies to other medications. It is important to note that over-the-counter (OTC) products can help relieve symptoms but do not treat the underlying infection.


Treatment Option	Mechanism of Action	Type	Key Considerations
Warm Compresses	Uses heat to help dissolve blockage and promote natural drainage of pus.	Home Remedy	The primary, most effective home treatment. Use for 10-15 minutes, 3-5 times daily.
Erythromycin Ointment	Antibiotic; stops the growth of bacteria causing the infection.	Prescription	A common first-line prescription antibiotic for styes.
Bacitracin Ointment	Antibiotic; kills bacteria by disrupting their cell wall formation.	Prescription	Another prescription antibiotic option, sometimes used if erythromycin is ineffective.
OTC Stye Ointments	Typically contain lubricants like mineral oil and petrolatum to soothe irritation.	Over-the-Counter	Provides symptomatic relief but does not contain antibiotics to treat the infection.
Oral Antibiotics	Systemic medication to fight more severe or widespread infections.	Prescription	Reserved for severe cases, recurrent styes, or if the infection spreads (e.g., preseptal cellulitis).

When to See a Doctor

Most styes resolve within one to two weeks with home care. However, you should consult a healthcare provider if:

The stye doesn't improve after a week of home treatment.
The pain or swelling worsens significantly.
Your vision is affected.
The entire eyelid becomes red and swollen.
The infection appears to be spreading.

An untreated or improperly managed stye can lead to complications such as a chalazion (a hardened, painless lump), or more seriously, the spread of infection to the surrounding eyelid tissues, a condition known as preseptal cellulitis. Never try to pop or squeeze a stye, as this can worsen the infection and cause it to spread.

Conclusion

So, does erythromycin treat styes? Yes, as a prescription antibiotic ointment, erythromycin is an effective and widely used treatment for the bacterial infections that cause styes. By halting bacterial growth, it helps resolve the infection, reduce symptoms, and prevent complications. For best results, it should be used as prescribed by a doctor, often in conjunction with warm compresses and good eyelid hygiene. If symptoms persist or worsen, professional medical advice is essential.

For more information on eye conditions, you can visit the American Academy of Ophthalmology.

Frequently Asked Questions

No, erythromycin ophthalmic ointment is a prescription medication and cannot be purchased over the counter. You must see a healthcare provider to get a prescription.

With proper application as directed by a healthcare professional, you should see improvement within a few days. The full course of treatment is typically prescribed for a specific duration. If there's no improvement as expected, you should contact your doctor.

A stye is most often caused by a bacterial infection in an oil gland or eyelash follicle on the eyelid. The bacterium Staphylococcus is the most common cause.

Styes are generally not considered contagious, but the bacteria from them can be spread. It's important to wash your hands after touching a stye and avoid sharing towels or makeup.

If left untreated, a stye can sometimes lead to complications such as a chalazion (a hardened cyst) or, in rare cases, spread to become a more serious infection called preseptal cellulitis.

Yes, it is recommended to avoid wearing contact lenses while you have a stye and are using treatment like erythromycin ointment to prevent further irritation and contamination.

A stye (hordeolum) is a painful bacterial infection that appears at the eyelid's edge. A chalazion is a blocked oil gland that is typically not painful and appears further back on the eyelid.