This medicine contains 2 antibiotics called Flucloxacillin and Ampicillin. This combination of Flucloxacillin and Ampicillin is also known as Co-Fluampicil. This medicine belongs to a group of antibiotics called the penicillins. Co-Fluampicil is used to treat certain bacterial infections of the ear, nose, throat, lungs, skin or bladder. interaction: Do not take antacids together with Co-Fluampicil. Antacids could reduce the effectiveness of Co-Fluampicil. If you must take antacids, take them at least 1 hour before or 2 hours after Co-Fluampicil. Inform your doctor if you are taking birth-control pills that contain oestrogen. Co-Fluampicil may decrease the effectiveness of these pills. You may wish to discuss additional birth-control methods with your doctor or pharmacist.