Well, if you're dead against it, you have the last word on medication, as the parent you can refuse it, but a visit to the GP wouldn't hurt, at least to rule out any recurrent water infection, or perhaps a developmental delay.
Does she know to wipe her bottom from front to back? This can be the cause of irritation and infection in little girls who are just learning to be responsible for their own hygiene. Perhaps using moist toilet wipes may help here too.
She is still very young, I'm working as a student Teaching Assistant in primary school, and even in the 7 year olds we do get some kids who have accidents. Perhaps this is just something that she will grow out of.
