This often settles after the first cycle but if it recurs you may try taking the pill at night or possibly switching to a lower dose pill. Do not forget that vomiting can interfere with pill absorption. Weight gain may be a problem for some. This is usually due to an increased appetite and responds to dieting. Occasionally a different brand of pill may help.
Women taking the pill have more episodes of cystitis.
Make sure that you empty your bladder after sex to minimise this. The pill does not cause epilepsy. Finally, there is a possibility that you become drunk more easily whilst taking the pill. The liver turns excess alcohol into waste products less efficiently when the contraceptive pill is being taken.