Penicillin Reaction or side affect?

[HaveYouMetTed]

I'm not sure what to do here with it being Sunday(no pharmacy open/no walk in centre in area)
Baby was given amoxicillin on Wednesday for a chest infection, hasn't been showing signs of improvement in that very upset most of day with a few brighter moments, not eating (having plenty of bf though) and runny nappy but only once a day so not runs all day.
This morning rash is all over, particularly on scalp.
I had been treating runny nappy etc as a side affect of antibiotics but now as everything is worse I'm wondering if the upset every day, particularly bad this morning, and rash is an allergic reaction?
I can call to get baby seen again tomorrow but should I stop the antibiotic in the meantime? I know it will have been fighting the infection despite causing the upset.
Obviously don't want to jump to conclusions and have baby unnecessarily marked as allergic as I believe other antibiotics are known to be less affective than penicillin.
(This is third time on amoxicillin)

the rash sounds like a post viral rash to me. i assume you have checked that it blanches when pressed?

can you phone 111 and seek advice on what to do re the antibiotics?

failing that, stop today and dr first thing.

I was also thinking it might be a post viral rash. Go to a pharmacist today and ask their opinion.

Yes done rash test etc (baby had meningitis when v small so I'm hyper sensitive to that)

Could be viral but doesn't look like when other DC have had a viral rash.

I'll phone 111. How that didn't occur to me I will never know
I was never a panicker with other DC!

Thank you

Glad you're phoning 111. My Dd is allergic to penicillin but the rash came up very quickly after the first dose - like within a couple of hours.

Was advised it's likely to be a side affect & not an allergic reaction as it's taken since Wed to come up.
To keep giving amoxicillin today as could do more harm if infection gets worse again but if rash still there I will go to go tomorrow.
Thank you for the replies