O que é Nystan?
Nystan (nystatin) is a polyene antifungal antibiotic derived from Streptomyces noursei, a soil bacterium. It is one of the oldest antifungal medicamentos in clinical use, having been in therapeutic use since the 1950s, and remains relevant today as an effective tratamento for localised Candida infections.
Nystatin is listed on the WHO Model List of Essential Medicines. Its key characteristic is that it is essentially non-absorbable — when taken orally or applied topically, it acts exclusively at the site of application with negligible systemic absorption. This makes it particularly valuable in situations where systemic antifungal exposure should be minimised.
Como funciona Nystan work?
Nystatin belongs to the polyene class of antifungals and works through a different mechanism to azole antifungals (such as fluconazole or clotrimazole):
- Direct membrane binding: Nystatin binds directly and irreversibly to ergosterol, the principal sterol component of the fungal cell membrane. This binding does not require activation by fungal enzymes.
- Membrane pore formation: The binding of multiple nystatin molecules to ergosterol creates channels (pores) in the fungal cell membrane.
- Loss of membrane integrity: These pores allow essential intracellular electrolytes and molecules (potassium ions, small proteins) to leak out of the fungal cell.
- Fungal cell death: The resulting disruption of osmotic balance and loss of vital cellular contents leads to fungal cell death (fungicidal effect).
Because human cells contain cholesterol rather than ergosterol as their primary membrane sterol, nystatin has very low affinity for human cell membranes, explaining its selectivity against fungi.
Why nystatin is not significantly absorbed systemically: Nystatin’s large molecular structure and polyene chemical properties prevent it from crossing mucosal barriers or intact skin in clinically meaningful amounts. This is both its limitation (it cannot treat systemic fungal infections) and its advantage (minimal systemic efeito secundários and drug interactions).
Para quem é Nystan for?
Nystatin is indicated for localised Candida infections in adults and children:
- Oral candidiasis (oral thrush): Oral suspension — swish and swallow technique, four times daily
- Vaginal candidiasis: Vaginal pessaries — typically 14-night course; suitable option in pregnancy
- Skin candidiasis: Topical creme or powder for candidal intertrigo, nappy rash, candidal paronychia
- Gastrointestinal candidiasis: Oral comprimidos or suspension to treat candidal overgrowth in the gut (in immunocompromised pacientes or following prolonged antibiotic courses)
Nystatin is not appropriate for:
- Systemic (bloodstream) candida infections — requires systemic antifungal agents under specialist care
- Dermatophyte infections such as athlete’s foot or ringworm (nystatin is not effective against dermatophytes)
- Infections caused by organisms other than Candida
Dosagem
| Formulation / Indication | Dose | Duration |
|---|---|---|
| Oral suspension (oral thrush) | 100,000 units (1 mL) four times daily | 7–14 days |
| Vaginal pessaries | 100,000 units (1 pessary) per night | 14 nights |
| Topical creme (skin candida) | Apply 2–4 times daily | Until resolved (often 2–4 weeks) |
| Oral comprimidos (GI candida) | 500,000 units (1 comprimido) four times daily | As directed by médico |
Oral suspension administration: The suspension should be shaken well before use. Place the dose in the mouth, swish it around all oral surfaces (teeth, gums, inside cheeks, tongue) for as long as possible, then swallow. Continue for 48 hours after symptoms resolve.
Vaginal pessaries: Insert high into the vagina at bedtime using the applicator provided.
Efeitos secundários
Nystatin is very well tolerated due to its minimal systemic absorption.
Oral suspension / comprimidos
- Nausea (uncommon)
- Vomiting (uncommon)
- Diarrhoea (uncommon at standard doses)
- Oral irritation or burning sensation (mild)
Vaginal pessaries
- Mild vaginal burning or irritation
- Increased vaginal discharge (mild)
Topical creme
- Local skin irritation, burning, or itching at the application site
- Rash (rare)
Systemic efeito secundários
Systemic efeito secundários are extremely rare at standard doses due to negligible absorption. At very high oral doses, gastrointestinal disturbance and hypersensitivity reactions have been reported rarely.
Nystan vs alternativas antifungal tratamentos
| Treatment | Active Ingredient | Mechanism | Absorbed Systemically? | Key Use |
|---|---|---|---|---|
| Nystan | Nystatin | Ergosterol binding (polyene) | No | Localised Candida |
| Canesten Gyno | Clotrimazole | Ergosterol synthesis inhibition (azole) | Minimally | Vaginal/skin Candida |
| Diflucan | Fluconazole | Ergosterol synthesis inhibition (azole) | Yes (oral) | Vaginal/systemic Candida |
| Terbinafine | Terbinafine | Ergosterol synthesis inhibition (allylamine) | Yes (oral) | Dermatophytes (nail/skin) |
Nystan vs Canesten Gyno / Diflucan for vaginal thrush: Azole tratamentos (clotrimazole, fluconazole) are generally preferred for vaginal candidiasis due to shorter tratamento courses and high efficacy. Nystatin’s 14-night course is less convenient but remains a valid option when azoles are not appropriate — for example, in documented azole allergy or when minimal systemic exposure is a priority.
Nystatin’s niche: Its non-absorbable nature makes it the preferred antifungal for treating localised Candida without any systemic drug exposure — a consideration particularly relevant in pregnancy and in pacientes on complex drug regimens where systemic azole drug interactions are a concern.
Como aceder a Nystan online na Europa
Nystan is a medicamento sujeito a receita médica (POM) in most estados-membros da UE. It cannot legally be dispensed without a valid receita médica from a licensed medical professional.
Prescrivia operates as a technology intermediary: we do not prescribe medicamentos, employ médicos, or sell medicamentos. Our platform connects pacientes with independent EU-registered médicos who can conduct confidential online health assessments.
The process:
- Complete uma avaliação de saúde: Describe your symptoms, relevant history, and any other medications or allergies.
- Avaliação médica: An independent EU-registered médico reviews your assessment. If nystatin is clinically appropriate, they may issue a receita médica.
- Dispensa na farmácia: The receita médica is sent to a licensed EU farmácia partner for dispensing and direct delivery.
Important: A Prescrivia não garante that a receita médica will be issued. All prescribing decisions are made independently by qualified medical professionals.
Informação de segurança importante
Informe o seu médico before using Nystan if you:
- Are pregnant or breastfeeding (topical and vaginal nystatin is generally considered safe; a médico should confirm the appropriate formulation)
- Have any known allergy to nystatin or other antifungal medicamentos
- Experience symptoms that could indicate an infection other than Candida — diagnosis should be confirmed before starting tratamento
- Have had recurrent Candida infections (investigation of underlying causes may be warranted)
Interações medicamentosas: Due to negligible systemic absorption, clinically significant drug interactions with nystatin are not expected. This is a notable advantage over systemic azoles, which have multiple drug interactions.
Treatment failure: If symptoms do not improve after completing the recommended course, consult a médico. The infection may not be caused by Candida, the causative organism may have reduced susceptibility to nystatin, or there may be an underlying condition predisposing to recurrence.
Fontes
Medical information on this page is based on the following sources:
- Agência Europeia de Medicamentos (EMA). Nystatin — Summary of Product Characteristics. Available at: ema.europa.eu
- Organização Mundial da Saúde (WHO). WHO Model List of Essential Medicines. 22nd edition, 2021. who.int
- Pappas PG, et al. Clinical Practice Guidelines for the Management of Candidiasis: 2016 Update by the Infectious Diseases Society of America (IDSA). Clinical Infectious Diseases. 2016.
This content is reviewed periodically to reflect updated clinical guidance. It is provided for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional for advice relevant to your individual health circumstances.
Frequently asked questions
- O que é Nystan (Nystatin) utilizado para?
- Nystan (nystatin) is an antifungal medicamento used to treat Candida infections affecting the mouth and throat (oral thrush), the vagina and vulva (vaginal candidiasis), the skin, and the gastrointestinal tract. It is available in several formulations: oral suspension, comprimidos, vaginal pessaries, and topical creme, making it versatile across different types of candidal infection.
- Why is Nystatin sometimes preferred over other antifungals?
- Nystatin is not significantly absorbed from the gut, skin, or mucous membranes, which means it acts locally at the site of infection with very low systemic exposure. This makes it a useful option when systemic antifungal exposure is undesirable — for example, in pacientes with certain drug interactions that would be a concern with oral fluconazole, or in specific situations during pregnancy where local vaginal tratamento is preferred.
- Quanto tempo dura a Nystatin course take?
- For vaginal candidiasis, nystatin pessaries are typically utilizado para 14 nights, which is longer than azole tratamentos such as clotrimazole or fluconazole. For oral thrush, nystatin oral suspension is used four times daily until symptoms resolve, typically for 7–14 days. Skin infections may require several weeks of topical tratamento.
- Is Nystatin safe in pregnancy?
- Vaginal nystatin pessaries and topical nystatin creme are considered appropriate options during pregnancy, as systemic absorption is negligible. Oral nystatin suspension is also used during pregnancy for oral thrush. A médico should always be consulted to confirm the diagnosis and appropriate formulation before starting tratamento during pregnancy.
- Posso obter Nystan online na Europa?
- Nystan is a medicamento sujeito a receita médica in most estados-membros da UE. You can access it through online intermediary platforms that connect you with independent EU-registered médicos for a confidential assessment and, if clinically appropriate, a receita médica.
Tratamentos
A Prescrivia é apenas uma plataforma intermediária. Não prestamos serviços médicos, não prescrevemos tratamentos nem dispensamos medicamentos. Todas as decisões médicas são tomadas por médicos independentes registados na UE. Todos os medicamentos são dispensados por farmácias licenciadas na UE. Esta plataforma facilita a ligação entre pacientes e prestadores de cuidados de saúde.