Betamethasone (Topical Solution & Ear Drops)

What Is Betamethasone and What Is It Used For?

Betamethasone is a potent topical corticosteroid (Group III) that works by suppressing inflammation and reducing itching in the skin. It is primarily prescribed as a cutaneous solution for inflammatory scalp conditions and as ear drops for ear canal inflammation.

Topical corticosteroids are among the most commonly prescribed treatments for inflammatory skin conditions worldwide, and betamethasone is one of the most established and widely used agents in this class. The medication is available as betamethasone valerate, a synthetic ester of betamethasone that provides enhanced skin penetration and potent local anti-inflammatory effects while minimising systemic absorption when used correctly.

Betamethasone belongs to the Group III category of topical corticosteroids, placing it in the “potent” tier of a four-tier classification system used internationally to grade topical steroid strength. This potency classification is important because it determines which body areas the medication is appropriate for, how long it can safely be used, and what level of medical supervision is required. Betamethasone is included on the WHO Model List of Essential Medicines, reflecting its importance in global dermatological care.

When applied to the skin, betamethasone valerate binds to intracellular glucocorticoid receptors in keratinocytes and immune cells within the dermis and epidermis. This binding triggers a cascade of anti-inflammatory effects: it suppresses the production of pro-inflammatory cytokines such as interleukin-1 and tumour necrosis factor-alpha, inhibits the release of arachidonic acid metabolites (prostaglandins and leukotrienes), reduces capillary permeability (thereby decreasing swelling), and stabilises lysosomal membranes. The combined result is a rapid reduction in redness, swelling, itching, and scaling at the application site.

Common Uses

Betamethasone cutaneous solution and ear drops are prescribed for several conditions:

• Scalp psoriasis: One of the most common indications, betamethasone solution effectively reduces the thick, silvery scaling, redness, and itching associated with psoriasis of the scalp. It is often a first-line treatment for mild to moderate scalp psoriasis.
• Scalp eczema (seborrhoeic dermatitis): Reduces inflammation and itching in eczematous conditions affecting the scalp, including contact dermatitis and atopic dermatitis of the scalp region.
• Other inflammatory scalp conditions: May be prescribed for other dermatoses affecting the scalp where a potent anti-inflammatory effect is needed, as directed by a dermatologist.
• Otitis externa (ear canal inflammation): As ear drops, betamethasone treats inflammation of the outer ear canal, reducing swelling, pain, and discomfort. It is typically used after the ear canal has been cleaned by a healthcare professional.
• Other body areas: Although formulated primarily for the scalp, the solution may be applied to other body areas as specifically directed by a doctor, depending on the condition and its location.

The cutaneous solution formulation is specifically designed for use on hairy areas of the body where creams and ointments would be impractical. The liquid base allows the medication to penetrate through hair to reach the scalp surface directly, making it the preferred formulation for scalp conditions. For other body areas, betamethasone is also available in cream and ointment formulations, which may be more appropriate depending on the condition and location.

What Should You Know Before Using Betamethasone?

Before using betamethasone, tell your doctor about all medical conditions you have, especially skin infections, and all other medications you use. There are several important contraindications and precautions that your healthcare provider must evaluate to ensure this medication is safe and appropriate for you.

While topical corticosteroids are generally well tolerated when used correctly, betamethasone is a potent preparation that requires careful consideration of contraindications and precautions. Your doctor will assess your individual situation to determine whether betamethasone is the right treatment for you and will provide specific instructions about where, how often, and for how long to apply it.

Contraindications

Do not use betamethasone if:

• You are allergic to betamethasone or any of the other ingredients in the formulation, including isopropyl alcohol, carbomer, or sodium hydroxide.
• You have a perforated eardrum (tympanic membrane perforation) – the ear drops must not be used in this situation, as the solution could enter the middle ear and cause damage.
• You have an active skin infection at the application site (bacterial, viral, or fungal) that is not being treated simultaneously with appropriate anti-infective medication. Corticosteroids can mask and worsen infections.
• You have acne vulgaris – betamethasone can worsen acne and should not be used as a treatment for this condition.
• You have rosacea – a chronic facial skin condition characterised by redness and visible blood vessels. Topical corticosteroids can significantly worsen rosacea.
• You have perioral dermatitis (a rash around the mouth) – this condition is often triggered or exacerbated by topical corticosteroid use.
• You have itchy but non-inflamed skin – betamethasone treats inflammation, not simple itch without an inflammatory cause.
• The intended application area is the genital or perianal region – these sensitive mucosal areas are particularly susceptible to corticosteroid side effects.
• The patient is a child under 1 year of age – the risk of systemic absorption and adrenal suppression is significantly higher in infants.

Warnings and Precautions

Talk to your doctor before using betamethasone if any of the following apply to you, as special precautions or closer monitoring may be necessary:

• History of corticosteroid hypersensitivity: If you have previously experienced an allergic reaction to any corticosteroid preparation (cream, ointment, or solution), inform your doctor. Local hypersensitivity reactions including skin redness, rash, itching, hives, burning sensation, and contact eczema can occur. If any skin reaction develops during treatment, stop using betamethasone immediately and contact your doctor.
• Application near the eyes: Exercise extreme caution when applying betamethasone near the eyelids. Avoid getting the solution into the eyes, as prolonged ocular exposure to corticosteroids can cause elevated intraocular pressure (glaucoma) and clouding of the lens (cataracts). Contact your doctor immediately if you experience blurred vision or other visual disturbances during treatment.
• Use on the face: Prolonged use of potent topical corticosteroids on facial skin can lead to skin thinning (atrophy), visible blood vessels (telangiectasia), and worsening of pre-existing conditions. Sensitive areas including the face, armpits, and groin should only be treated for short periods.
• Psoriasis patients: If you have psoriasis, your doctor will want to monitor you more frequently. There is a risk of tolerance development (the medication becoming less effective over time) and rebound flare upon discontinuation. In very rare cases, treatment may trigger pustular psoriasis (a severe form characterised by pus-filled blisters).
• Venous leg ulcers: If you have dermatitis (skin inflammation) around a leg ulcer, using a topical corticosteroid near the wound increases the risk of allergic contact reactions and local infection.
• Occlusive dressings: Using betamethasone under occlusive dressings (including a child’s nappy/diaper) increases skin absorption and the risk of both local and systemic side effects. If occlusive dressings are prescribed, ensure the skin is thoroughly cleaned before each new dressing is applied. Do not use occlusive dressings on infected eczema.
• Prolonged or extensive use: Using high doses of betamethasone over large body surface areas or for extended periods can lead to sufficient systemic absorption to cause adrenal suppression and Cushing’s syndrome symptoms. These include weight gain with altered fat distribution (abdomen, neck, face), thin and fragile skin, increased body hair, decreased bone density, and high blood pressure. In children, growth suppression may also occur. If any of these effects are observed, contact your doctor for a gradual tapering plan.
• Infection masking: Corticosteroids can mask, activate, or worsen skin infections. If you develop signs of a new infection during treatment, consult your doctor promptly.

Pregnancy and Breastfeeding

If you are pregnant, breastfeeding, think you may be pregnant, or are planning to have a baby, consult your doctor or pharmacist before using betamethasone.

Pregnancy: The safety of topical betamethasone during pregnancy has not been fully established. Animal studies have shown that corticosteroids can affect foetal development, and while the risk from topical application is generally considered low, betamethasone should only be used during pregnancy if your doctor has specifically determined that the benefits outweigh the potential risks to the foetus. If prescribed, use the smallest amount for the shortest possible duration.

Breastfeeding: Small amounts of topical corticosteroids may be absorbed into the bloodstream and could potentially pass into breast milk. If your doctor determines that betamethasone is necessary during breastfeeding, do not apply it to the breasts to avoid accidental ingestion by the nursing infant. Discuss the risks and benefits with your healthcare provider.

Driving and Operating Machinery

Betamethasone cutaneous solution has no known effect on the ability to drive or operate machinery. The medication acts locally at the application site and does not typically cause drowsiness, dizziness, or other effects that would impair these activities.

How Does Betamethasone Interact with Other Drugs?

Betamethasone topical solution has fewer drug interactions than oral corticosteroids because it is applied to the skin rather than taken by mouth. However, some medications can still affect how betamethasone works or increase the risk of side effects, particularly drugs that inhibit the CYP3A4 enzyme system.

Because betamethasone is used topically, the extent of systemic absorption is generally low when the product is used as directed on small body surface areas for limited durations. However, when betamethasone is used extensively, on damaged or inflamed skin, under occlusive dressings, or for prolonged periods, systemic absorption can become clinically significant. In these situations, drug interactions that would normally apply to oral or injectable corticosteroids may become relevant.

The most important interactions involve drugs that inhibit the cytochrome P450 3A4 (CYP3A4) enzyme, which is responsible for metabolising betamethasone in the body. When these inhibitors are present, betamethasone levels in the bloodstream may increase, raising the risk of systemic corticosteroid side effects.

Notable Drug Interactions

The interactions listed above are most relevant when betamethasone is used over large body surface areas, on damaged or highly inflamed skin, under occlusive dressings, or for extended periods – situations where systemic absorption is increased. When betamethasone is applied to small areas of intact skin for short durations, clinically significant drug interactions are unlikely.

This is not a complete list of potential interactions. Always inform your doctor, pharmacist, or healthcare provider about all medications you are currently using, including prescription drugs, over-the-counter medicines, vitamins, herbal products, and other topical treatments. Never start, stop, or change any medication without first consulting your healthcare provider.

What Is the Correct Dosage of Betamethasone?

Always use betamethasone exactly as your doctor has prescribed. The dosage depends on the condition being treated and the area of application. Apply only the amount needed to thinly cover the affected area, and do not exceed 4 weeks of daily use without medical review.

The principle of topical corticosteroid use is to apply the minimum effective amount for the shortest necessary duration. This approach maximises therapeutic benefit while minimising the risk of side effects. Your doctor will determine the appropriate treatment regimen based on the specific condition, its severity, and the body area involved.

Scalp Treatment

Ear Canal Treatment

Other Body Areas

Elderly and Patients with Liver or Kidney Impairment

Missed Dose

If you forget to apply betamethasone, apply it as soon as you remember and then continue with your normal schedule. Do not apply extra medication to compensate for a missed dose – simply resume your regular application routine. Applying too much betamethasone at once does not improve effectiveness and increases the risk of side effects.

Overdose

If you have applied significantly more betamethasone than prescribed, or if someone (particularly a child) has accidentally swallowed the solution, contact your doctor, hospital, or poison control centre immediately for risk assessment and guidance. Chronic overuse of topical corticosteroids can lead to adrenal suppression and Cushing’s syndrome features. If you have been using betamethasone regularly and need to stop, your doctor will advise you to reduce the application frequency gradually rather than stopping abruptly.

What Are the Side Effects of Betamethasone?

Like all medicines, betamethasone can cause side effects, although not everyone experiences them. The risk of side effects increases when the medication is used over large areas, under occlusive dressings, or for prolonged periods.

Topical corticosteroid side effects are predominantly local (affecting the application site) and are largely dependent on the potency of the preparation, the duration of use, the body area treated, and whether occlusive dressings are employed. Facial skin, skin folds (armpits, groin), and damaged or inflamed skin absorb more medication and are at higher risk of local side effects. Systemic side effects are uncommon with topical use but can occur with extensive or prolonged treatment.

How Should You Store Betamethasone?

Store betamethasone out of the sight and reach of children. No special storage conditions are required, but take care due to the flammable nature of the solution.

Keep the betamethasone solution in its original container at room temperature. There are no specific temperature storage requirements, but the product should be stored away from direct sunlight and heat sources. Because the solution contains isopropyl alcohol, it is flammable and must be kept away from open flames, cigarettes, and other ignition sources.

Do not use the medication after the expiry date printed on the outer packaging (after “EXP”) and on the bottle label. The expiry date refers to the last day of the stated month. Once opened, the solution should be used within the timeframe specified on the packaging or as advised by your pharmacist.

Do not dispose of medications in wastewater or household waste. Ask your pharmacist about proper disposal methods for medicines you no longer need. These measures help protect the environment from pharmaceutical contamination.

What Does Betamethasone Contain?

The active substance is betamethasone (as betamethasone valerate). Each 1 ml of cutaneous solution contains betamethasone valerate equivalent to 1 mg of betamethasone.

Active Ingredient

Betamethasone valerate is a synthetic ester of the glucocorticoid betamethasone. The valerate ester form enhances skin penetration and provides sustained local anti-inflammatory activity. Each millilitre of the cutaneous solution delivers 1 mg of betamethasone (equivalent to approximately 1.22 mg of betamethasone valerate).

Inactive Ingredients (Excipients)

The other ingredients in the cutaneous solution are:

• Carbomer – a thickening agent that helps control the viscosity of the solution
• Isopropyl alcohol – a solvent that aids penetration and provides rapid evaporation (note: this makes the solution flammable)
• Sodium hydroxide – used to adjust the pH of the solution
• Purified water – the base solvent

The solution is a clear liquid supplied in a 100 ml plastic bottle with a plastic nozzle tip and plastic cap. If you are allergic to any of the listed ingredients, do not use this product and inform your doctor so an alternative treatment can be prescribed.