Nausea, vomiting, diarrhoea, fever, and body aches are all possible side effects of Ceftum. Dizziness and sleepiness are less likely to occur, especially at higher doses. Notify your doctor or pharmacist right once if any of these side effects persist or worsen. Also, Diarrhoea is the most prevalent adverse effect, which is usually minor and goes quickly. You should see your doctor if it develops severely or lasts more than 24 hours.