Metronidazole 400mg is a prescription antibiotic commonly used in the UK to treat a range of bacterial and parasitic infections, including dental infections, skin infections, pelvic infections, and certain gastrointestinal conditions. It works by stopping the growth of bacteria and parasites that cause illness. When buying Metronidazole 400mg in the UK, it is important to obtain it through a licensed pharmacy with a valid prescription from a healthcare professional.