As already pointed out, the 'g' on the prescription is latin for drop. I often see this on hospital prescriptions but guess you are a relatively young pharmacist ? Us 'older' pharmacists, (***Avoids looking in Johnep's direction***), are used to these latin abbreviations used primarily by older GPs and Hospital consultants. I am afraid it is your error.
Mind you, it can be confusing. I have recently seen the letter 'G' used in front of a Mercaptopurine script from a consultant. The pre-reg read it as '6' and labelled it as 6 x 50mg Mercaptopurine tablets daily !!!

I did point out that the 'G' was an old school way of writing 'Give'. Not only did she learn this, but also the maximum daily dose of mercaptopurine
Cheers
Stephen