Nystatin (Oral Suspension)

How it works

Nystatin binds to ergosterol in the fungal cell membrane, creating pores that disrupt membrane integrity and cause leakage of intracellular contents and fungal cell death.

Prescribing in practice

• It acts only on contact within the gastrointestinal tract and is negligibly absorbed, so it is effective for local oral and gut candidiasis but not for systemic fungal infection.
• The suspension should be retained in the mouth in contact with the affected areas before swallowing, and treatment continued for a short period after symptoms resolve to prevent relapse.
• It is generally very well tolerated, with occasional gastrointestinal upset or local irritation at higher doses.

Monitoring

Routine monitoring is not required; review response and consider an alternative or investigation for predisposing factors if the infection fails to clear.

Counselling the patient

• Hold the liquid in your mouth, swishing it around the affected areas, before swallowing.
• Keep taking it for a few days after the soreness clears to stop the infection coming back.
• If you wear dentures, clean them well as they can harbour the infection.

Evidence & guidelines

Topical antifungals such as nystatin are an established treatment for oropharyngeal candidiasis, with persistent or recurrent infection prompting a search for underlying causes.