The frequency of adverse events listed as follows is defined using the following convention: very common (≥1/10); common (≥1/100 to <1/10); uncommon (≥1/1,000 to <1/100), rare (≥1/10,000 to <1/1,000); very rare (<1/10,000), not known (cannot be estimated from the available data).
The frequency of systemic side/adverse effects is very rare since after intravaginal administration of metronidazole, very low plasma levels are observed (2%-12% compared to oral route). Miconazole nitrate can cause vaginal irritation (burning, itching) as all other imidazole derivative antifungal drugs applied intravaginally (2-6%). These symptoms are greatly reduced while the treatment continues. If there is severe irritation, the treatment should be stopped.
Undesirable effects regarding systemic use of active substances of Metronidazole + Miconazole (Metromic) 500 mg/100 mg and Metronidazole + Miconazole (Metromic Forte) 750 mg/200 mg Vaginal Suppositories are listed as follows:
Blood and lymphatic system disorders: Not known: Leucopenia.
Immune system disorders: Not known: Hypersensitivity reactions, allergic reactions, anaphylaxis may occur in severe cases.
Psychiatric disorders: Uncommon: Depression.
Very rare: Mental alterations.
Nervous system disorders: Common: Dizziness, headache.
Not known: Tiredness or weakness, ataxia, convulsion, peripheral neuropathy due to intensive and/or prolonged metronidazole therapy.
Gastrointestinal disorders: Not known: Taste changes, metallic taste, nausea, vomiting, constipation, dry mouth, diarrhea, lack of appetite, abdominal pain or cramp.
General disorders and administration site conditions: Very common: Vaginal discharge.
Common: Vaginitis, vulvovaginal irritation, pelvic discomfort.
Uncommon: Feeling of thirst.
Rare: Vaginal burning, itching, irritation, rash.
Not known: Local irritation and hypersensitivity, contact dermatitis.
These adverse effects are observed rarely since blood concentration of metronidazole and miconazole is much lower when administered via intravaginal route.