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A07AC comprises intestinal antiinfective medicines that are imidazole derivatives, currently represented by miconazole formulated for local action in the gastrointestinal tract. From a lactational-toxicological perspective, these preparations have minimal expected transfer into breast milk and a low theoretical risk for the breastfed infant when used as indicated.atcddd.fhi+3

ATC classification and group definition

A07 belongs to “Antidiarrheals, intestinal anti‑inflammatory/anti‑infective agents” within the Alimentary tract and metabolism main group.atcddd.fhi+1
Within A07, A07A covers “Intestinal antiinfectives”, a subgroup of locally acting antiinfective medicines distinct from systemic antiinfective agents classified in the J group.atcddd.fhi

A07AC is the chemical subgroup “Imidazole derivatives”, and according to the current ATC/DDD Index the only listed substance is miconazole (A07AC01).who+1
The WHO Collaborating Centre specifies that Defined Daily Doses (DDDs) for A07AC are based on treatment of gastrointestinal mycosis, underlining their local antifungal use in the gut.atcddd.fhi+1

Pharmacology and therapeutic use

Miconazole is an imidazole antifungal agent that inhibits ergosterol synthesis in fungal cell membranes by blocking cytochrome P450‑dependent enzymes, leading to impaired membrane function and fungal cell death.pmc.ncbi.nlm.nih+1
In A07AC formulations it is intended for local gastrointestinal action against fungal overgrowth or mycotic infections, with negligible systemic antifungal contribution compared with parenteral or high‑bioavailability oral imidazoles.who+1

Therapeutic indications typically include fungal infections of the gastrointestinal tract, such as Candida overgrowth, especially in patients receiving broad‑spectrum antibiotics or with local predisposing factors.atcddd.fhi+1
Use is generally short‑term, guided by clinical evaluation of diarrhoea or gastrointestinal discomfort and, when necessary, microbiological confirmation of fungal involvement.stjames+1

Formulations, dosage and administration

A07AC products are formulated for oral administration with the aim of local action in the intestinal lumen (for example suspensions, capsules or tablets designed for limited systemic absorption).atcddd.fhi+1
The DDD in the ATC/DDD index for miconazole A07AC01 is 1 g by oral route, defined for utilisation studies and not necessarily equal to the recommended patient dose.atcddd.fhi+1

In clinical practice dosing is individualised according to product characteristics, severity of symptoms, and patient factors such as age, comorbidities and concomitant medicines.ema.europa+1
Treatment duration is usually limited to the period necessary to control symptoms and eradicate local fungal infection, with reassessment if diarrhoea or gastrointestinal complaints persist.stjames+1

Pharmacokinetics and milk transfer

Intestinal miconazole preparations in A07AC are designed for local action and characteristically have very low systemic bioavailability.who+1
Limited absorption from the gastrointestinal tract results in low maternal plasma concentrations, which in turn restrict the amount potentially transferred into breast milk.stjames+1

Given the small molecular exposure and substantial first‑pass metabolism of absorbed fractions, the milk‑to‑plasma ratio is expected to be low, and infant exposure via breastfeeding is minimal.stjames+1
Moreover, miconazole is often used topically (oral, cutaneous, vaginal) with established low infant exposure in breastfeeding women, supporting the safety profile of locally acting intestinal formulations.stjames+1

Toxicological profile and adverse effects

Systemically absorbed imidazoles can cause hepatic enzyme perturbations, gastrointestinal upset, skin reactions and, rarely, more serious hypersensitivity reactions.ema.europa+1
For A07AC intestinal preparations with low systemic absorption, adverse effects are predominantly local gastrointestinal, such as nausea, abdominal discomfort or altered bowel habit.pmc.ncbi.nlm.nih+1

Serious toxicity in adults is uncommon when used at recommended doses, but caution is advisable in patients with significant hepatic disease or known imidazole hypersensitivity.ema.europa+1
In breastfed infants, relevant toxicological effects are unlikely due to minimal exposure; theoretical concerns include alteration of gut flora or mild gastrointestinal symptoms, but clinical reports are rare.stjames+1

Lactational risk assessment

General lactation pharmacology shows that most medicines pass into human milk in low amounts, and breastfeeding is rarely absolutely contraindicated.stjames+1
For locally acting intestinal antiinfectives like A07AC miconazole, poor systemic absorption and low maternal plasma levels support a favourable lactational safety profile, with negligible infant systemic exposure.atcddd.fhi+1

Based on mechanism of action, pharmacokinetics and clinical experience with topical miconazole, the risk of clinically significant adverse effects in breastfed infants is expected to be very low when the medicine is used short‑term and within therapeutic doses.stjames+1
Therefore, continuation of breastfeeding is usually compatible with maternal A07AC therapy; monitoring of the infant’s gastrointestinal status (stools, feeding, general wellbeing) is prudent but routine interruption of breastfeeding is not required.stjames+1

Clinical recommendations in breastfeeding

When an A07AC imidazole intestinal preparation is indicated in a breastfeeding woman, it can generally be prescribed without stopping breastfeeding, provided there are no additional contraindications.stjames+1
Clinicians should verify the specific product formulation, dose and duration, considering maternal factors such as hepatic function, concurrent hepatotoxic drugs and overall medication burden.ema.europa+1

Infants should be observed for changes in stool pattern, feeding difficulty, or signs of intolerance, although these events are unlikely and non‑specific.stjames+1
If clinically significant symptoms arise temporally related to maternal therapy, individual risk–benefit reassessment is recommended, including consideration of discontinuation of the medicine or temporary pumping and discarding, depending on severity.ema.europa+1

Contraindications and precautions

Standard contraindications to A07AC imidazole derivatives include known hypersensitivity to miconazole or other imidazoles and severe, active liver disease.ema.europa+1
Caution is warranted in concomitant use with medicines that strongly affect hepatic metabolism or carry their own significant hepatotoxic risk, although this is more relevant for systemically absorbed imidazoles than for low‑bioavailability intestinal preparations.ema.europa+1

In lactating women, contraindications mirror those in the general adult population; breastfeeding itself is not a contraindication to A07AC therapy.stjames+1
Patients should be counselled about correct administration, awareness of possible adverse effects, and the absence of evidence for meaningful harm to the breastfed infant at therapeutic doses.stjames+1

Summary for practice and education

A07AC comprises intestinal antiinfective imidazole derivatives, currently represented by locally acting oral miconazole for treatment of gastrointestinal mycosis.who+1
With very low systemic absorption, these preparations yield minimal drug transfer into breast milk and are considered compatible with breastfeeding in most clinical scenarios, especially when used short‑term and under medical supervision.stjames+1

Healthcare professionals should integrate ATC classification knowledge with lactational pharmacology principles, recognising that locally acting intestinal agents typically pose low risk to breastfed infants.who+1
Appropriate counselling supports continuation of breastfeeding, vigilant but proportionate monitoring of the infant, and rational avoidance of unnecessary interruption of lactation.stjames+1