Hiya! Great to hear you're interested in pharmacy

I have just finished my 4th year of pharmacy at Bath so hopefully can provide some insight.
Pharmacy is a degree which requires a lot of time commitment, so I would advise against taking up a job which requires you to work a lot of hours. As an estimate, I would suggest no more than 8/ 10 hours a week if you want to keep on top of studying. Some of my friends work in a pharmacy for 8 hours on a Saturday and that seems to be manageable and also might assist with learning on the course.
As mentioned above, the timetable is likely to change every semester (at least it does at Bath), so it would be difficult to commit to working a specific shift in the week. Travelling for placements might also affect your ability to work as it's likely you will be located away from your university at least once, so work would have to be flexible around that.
I also agree that finding a job through the uni is more likely to be flexible around your schedule. For example my work as a student ambassador allows me to choose when I post on platforms like this so it really could not be more flexible. At Bath, a lot of students also choose to help out at open days as it is a very easy way to earn some money.
Here is a link to apply to be a student ambassador at Bath in case you or anyone else is interested and you can find more vacancies on campus
here. Overall, I would definitely recommend finding out what jobs are available at the uni you end up at but advise you to keep the hours you commit to minimal.
Let me know if you have any more questions about pharmacy or studying at Bath

Lauren, University of Bath