Donaxyl (Dequalinium Chloride)

What Is Donaxyl and What Is It Used For?

Donaxyl belongs to the family of anti-infective and antiseptic medications designed specifically for vaginal use. The active substance, dequalinium chloride, is a quaternary ammonium compound with broad-spectrum antimicrobial activity. It is particularly effective against the anaerobic bacteria most commonly associated with bacterial vaginosis, including Gardnerella vaginalis, Atopobium vaginae, and various Prevotella and Mobiluncus species.

Bacterial vaginosis is the most common vaginal infection in women of reproductive age, affecting an estimated 20–30% of women worldwide at any given time according to WHO data. BV occurs when the normal balance of vaginal bacteria is disrupted. Under healthy conditions, the vagina is predominantly colonized by Lactobacillus species, which produce lactic acid and hydrogen peroxide, maintaining an acidic environment (pH 3.8–4.5) that protects against pathogenic organisms. When this balance shifts and the pH becomes more alkaline, lactobacilli are displaced by anaerobic bacteria, leading to BV.

The hallmark signs and symptoms of bacterial vaginosis include a thin, grayish-white homogeneous vaginal discharge that differs from normal secretions, and a characteristic unpleasant “fishy” odor that may be particularly noticeable after sexual intercourse. Some women also experience mild vaginal discomfort and itching, though notably without the significant redness or inflammation typically seen in yeast infections or sexually transmitted infections. Many women with BV, however, are asymptomatic.

Unlike systemic antibiotics such as oral metronidazole or clindamycin, Donaxyl acts exclusively at the local level. The vaginal tablet dissolves within the vaginal canal, releasing dequalinium chloride directly at the site of infection. This local mechanism of action means that systemic absorption is minimal, which contributes to the favorable side effect profile and reduces the risk of systemic adverse events such as gastrointestinal disturbance, which is common with oral antibiotic therapy.

An important clinical advantage of dequalinium chloride over traditional antibiotics is the low risk of antimicrobial resistance development. Because it works through a non-specific mechanism (disruption of bacterial cell membranes) rather than targeting specific metabolic pathways, bacteria are unlikely to develop resistance. This makes Donaxyl a particularly attractive option for women with recurrent BV who may have concerns about repeated antibiotic courses.

What Should You Know Before Using Donaxyl?

Contraindications

There are several situations in which Donaxyl should not be used. Understanding these contraindications is essential for safe and effective treatment. The medication is contraindicated in the following circumstances:

• Allergy to dequalinium chloride or any of the excipients (lactose monohydrate, microcrystalline cellulose, or magnesium stearate)
• Vaginal or cervical ulceration — pre-existing wounds or ulcers in the vagina or on the cervix. If you suspect vaginal ulceration, consult a healthcare provider before using this product
• Pre-menarche — the product should not be used by girls who have not yet had their first menstrual period

If you are uncertain about whether you have vaginal ulcers or another condition that might contraindicate use, it is important to consult your healthcare provider. Conditions such as vaginal atrophy (common in postmenopausal women) may present with tissue fragility that requires assessment before starting treatment.

Warnings and Precautions

Several important precautions should be observed during treatment with Donaxyl to ensure optimal efficacy and safety:

• Avoid intravaginal products: The use of soap, spermicidal agents, and vaginal douches (vaginal washing) within the vagina is not recommended during treatment, as these products may interfere with the local antimicrobial action of dequalinium chloride.
• Sexual health considerations: If you have recently had unprotected sexual intercourse and suspect you may have acquired a sexually transmitted infection (STI), consult a healthcare provider. BV symptoms can overlap with those of certain STIs, and appropriate testing may be warranted.
• Intercourse during treatment: As with all vaginal infections, it is generally recommended to avoid unprotected intercourse during the treatment period to optimize treatment outcomes and reduce the risk of re-infection.
• Latex condoms: Donaxyl does not reduce the effectiveness of latex condoms. This has been specifically tested and confirmed.
• Non-latex barrier methods: The product may reduce the effectiveness of condoms or diaphragms made from materials other than latex. If using non-latex barrier contraceptives, alternative contraception should be employed for at least 12 hours after the last treatment.
• Menstruation: Treatment should be interrupted during the period of heaviest menstrual bleeding and resumed afterward, as heavy bleeding may wash out the tablet before adequate dissolution and absorption can occur.
• Labor and delivery: Do not use Donaxyl within 12 hours before an expected delivery to minimize potential exposure of the newborn to dequalinium chloride. Inform your healthcare provider if you have recently used this medication.
• Persistent symptoms: If symptoms persist after completing the full 6-day course or if symptoms recur, consult a healthcare provider for further evaluation. Recurrent BV may require alternative or combination therapy.

Women over 55 years: There is insufficient clinical experience with Donaxyl in women over 55 years of age. If you are in this age group, consult your healthcare provider before use, as postmenopausal vaginal changes (including atrophy and altered pH) may affect both the appropriateness of this treatment and the underlying diagnosis.

Children and adolescents under 18: There is insufficient clinical experience in children and adolescents under 18 years of age. This product is not recommended for use in this age group.

Pregnancy and Breastfeeding

If you are pregnant, breastfeeding, think you may be pregnant, or are planning to become pregnant, consult your healthcare provider or midwife before using Donaxyl.

Based on available clinical experience and the fact that Donaxyl acts locally with minimal systemic absorption, no harmful effects on pregnancy, the unborn child, or the breastfed infant are expected. Dequalinium chloride exerts its pharmacological action within the vaginal canal, and the amount of drug that reaches the systemic circulation is negligible.

However, as with all medications during pregnancy and breastfeeding, Donaxyl should only be used when there is a clear medical need. Untreated bacterial vaginosis during pregnancy has been associated with adverse obstetric outcomes including preterm birth, premature rupture of membranes, and low birth weight, making appropriate treatment an important consideration. Always discuss the benefits and risks with your healthcare provider.

Driving and Operating Machinery

Donaxyl is not expected to affect your ability to drive or operate machinery. No studies specifically evaluating this have been conducted; however, given the local route of administration and minimal systemic absorption, no impairment is anticipated.

How Does Donaxyl Interact with Other Drugs?

One of the significant clinical advantages of Donaxyl is its very low potential for drug interactions. Because dequalinium chloride acts locally within the vagina and undergoes minimal systemic absorption, it is not expected to interact with orally administered medications, injectable drugs, or other systemically acting therapies. This makes it a particularly suitable option for women taking multiple medications.

The pharmaceutical characteristics of dequalinium chloride support this favorable interaction profile. As a quaternary ammonium compound, it does not undergo hepatic metabolism via cytochrome P450 enzymes, which are responsible for the vast majority of clinically significant drug-drug interactions. It is not known to inhibit or induce any CYP450 isoforms, and it does not affect plasma protein binding of other medications.

Local Interactions to Avoid

While systemic drug interactions are not a concern, certain locally applied vaginal products should be avoided during Donaxyl treatment as they may interfere with its antimicrobial action:

If you are using any other vaginal medication (such as antifungal pessaries, vaginal hormone therapy, or other antimicrobial preparations), discuss the timing and potential interactions with your healthcare provider or pharmacist. In general, it is advisable to avoid concurrent use of multiple intravaginal products unless specifically directed by a healthcare provider.

What Is the Correct Dosage of Donaxyl?

Always use Donaxyl exactly as described in the patient information leaflet or as directed by your healthcare provider or pharmacist. The treatment regimen is straightforward, but proper technique and adherence to the full course are essential for optimal outcomes.

Adults (Women Aged 18–55)

The 6-day treatment course has been established through clinical trials as the optimal duration for achieving bacteriological cure and symptom resolution. Shortening the treatment course increases the risk of symptom recurrence and treatment failure. Even if symptoms such as discharge, odor, and discomfort resolve within the first 2–3 days, it is essential to complete all 6 days of treatment.

Step-by-Step Instructions for Use

1. Wash your hands thoroughly before opening the blister packaging.
2. Remove one tablet from the blister pack.
3. Lie down in a comfortable resting position with your legs slightly drawn up.
4. Insert the vaginal tablet deep into the vagina using your finger.
5. If vaginal dryness is present: The tablet may not dissolve properly in dry conditions and could be expelled intact, reducing treatment effectiveness. In this case, moisten the tablet with a single drop of water before insertion.
6. Repeat every evening for 6 consecutive days.

Use During Menstruation

Treatment should be interrupted during the heaviest days of menstrual bleeding and resumed once the heavy flow subsides. Heavy menstrual flow can physically wash out the tablet before the active ingredient has been adequately released, potentially reducing treatment efficacy. Light menstrual flow typically does not require interruption of treatment.

Children and Adolescents

Donaxyl is not recommended for use in children and adolescents under 18 years of age due to insufficient clinical experience in this population. Alternative treatments should be discussed with a healthcare provider for patients in this age group who present with BV.

Women Over 55 Years

There is insufficient clinical data for women over 55 years of age. Postmenopausal women should consult their healthcare provider before using Donaxyl, as vaginal atrophy and altered vaginal pH may affect both the underlying diagnosis and the appropriateness of treatment. Conditions that mimic BV, such as atrophic vaginitis, are more common in this age group and require different management.

Missed Dose

If you forget to use a tablet on one evening, do not use a double dose to compensate. Simply insert a tablet the following evening as usual and continue the remaining course. The total number of tablets used should still be 6 for a complete treatment course, so consider extending treatment by one day to account for the missed dose.

Overdose

If a higher daily dose is used or if the medication is used for longer than recommended, the risk of vaginal ulceration may increase. If Donaxyl vaginal tablets are accidentally ingested orally (for example, if a child swallows a tablet), contact a healthcare provider, hospital emergency department, or poison control center immediately for risk assessment and advice.

What Are the Side Effects of Donaxyl?

Like all medicines, Donaxyl can cause side effects, although not everyone experiences them. Most reported side effects are mild and self-limiting, typically resolving during or shortly after the completion of the treatment course. Understanding the frequency and nature of potential side effects helps you distinguish between expected treatment effects and situations that warrant medical attention.

It is important to note that at the beginning of treatment, signs of vaginal infection (such as itching, burning, and discharge) may temporarily worsen before they begin to improve. This initial exacerbation is a known phenomenon and does not indicate treatment failure. You should continue with the treatment course, but if symptoms become severe or persist beyond the treatment period, contact your healthcare provider promptly.

Vaginal Yeast Infection (Candidiasis)

One of the most clinically significant side effects of Donaxyl therapy is the development of a secondary vaginal yeast infection, which occurs in a common frequency (up to 1 in 10 users). This is not unique to dequalinium chloride; it is a well-known phenomenon with virtually all antimicrobial treatments for BV, including metronidazole and clindamycin. The antimicrobial action that eliminates BV-causing bacteria can simultaneously disrupt the ecological balance, creating conditions favorable for Candida overgrowth.

Symptoms of a secondary yeast infection include thick, white, cottage-cheese-like discharge, intense itching, redness, and vulvar irritation. If you develop these symptoms during or after Donaxyl treatment, consult your healthcare provider or pharmacist, as antifungal treatment may be required.

When to Seek Medical Advice

Contact your healthcare provider if you experience any of the following:

• Symptoms that worsen significantly or do not improve after completing the full course
• Signs of an allergic reaction (widespread rash, significant swelling, difficulty breathing)
• Unusual vaginal bleeding not related to menstruation
• Severe vaginal pain or new onset of fever
• Suspected vaginal ulceration (burning pain, visible sores)

How Should You Store Donaxyl?

Proper storage of Donaxyl ensures that the medication remains effective throughout its shelf life. Follow these storage guidelines to maintain the quality and potency of the vaginal tablets:

• Keep out of sight and reach of children. Store in a location that children cannot access, as accidental oral ingestion requires medical assessment.
• No special storage conditions required. Donaxyl can be stored at normal room temperature. There is no need for refrigeration or protection from light under standard conditions.
• Check the expiry date. Do not use Donaxyl after the expiry date printed on the carton and blister packaging. The expiry date refers to the last day of the stated month.
• Keep in the original packaging. Leave the tablets in the blister pack until you are ready to use them to protect them from moisture and physical damage.
• Proper disposal. Do not dispose of unused or expired tablets by flushing them down the toilet or throwing them in household waste. Return any unused medicine to your pharmacist for safe disposal in accordance with local regulations to help protect the environment.

Donaxyl vaginal tablets are supplied in a single blister pack containing 6 tablets — the exact number required for one complete treatment course. Each tablet is white or nearly white, oval, and biconvex, measuring approximately 19 mm in length, 12 mm in width, and 6.3 mm in thickness.

What Does Donaxyl Contain?

Active Ingredient

Each vaginal tablet contains 10 mg dequalinium chloride. Dequalinium chloride (chemical name: 1,1′-(decane-1,10-diyl)bis(4-amino-2-methylquinolinium) dichloride) is a bis-quaternary ammonium compound. It has been used in medicine since the 1950s, initially as a broad-spectrum antiseptic in throat lozenges and wound care preparations. Its application in vaginal therapy leverages its potent antimicrobial properties against the specific pathogens implicated in bacterial vaginosis.

The mechanism of action involves insertion of the dequalinium cation into the bacterial cell membrane, causing depolarization, loss of membrane integrity, and ultimately cell lysis. This non-specific membrane-disrupting action is effective against a broad range of gram-positive and gram-negative bacteria, as well as fungi, while the risk of resistance development remains very low.

Inactive Ingredients (Excipients)

The excipients used in Donaxyl are well-established pharmaceutical ingredients with a long history of safe use. Importantly, the tablet formulation does not contain any preservatives, artificial colors, or fragrances. The non-dissolving excipient residues are responsible for the occasional appearance of tablet remnants in underwear, which is a cosmetic rather than a clinical concern.

International Brand Names

Donaxyl is marketed under different brand names across European countries. The same formulation (10 mg dequalinium chloride vaginal tablets) is known as:

• Fluomizin — Germany, Austria, Belgium, Italy, Luxembourg, Poland, Slovakia, Spain, France, Croatia, Slovenia, Netherlands, Hungary, United Kingdom
• Donaxyl — Finland, Norway, Sweden, Estonia, Lithuania, Latvia
• Naxyl — Czech Republic

All brand names refer to the same pharmaceutical product containing 10 mg of dequalinium chloride per vaginal tablet, manufactured by Haupt Pharma Amareg GmbH in Regensburg, Germany. The product is authorized and available across the European Economic Area (EEA).