Tap on your med in the 'Medications' list

Tap the pen icon in the upper right corner to edit

Tap on 'Reminder Times' and tap where it says 'Take x pills'

On the bottom of the pop-out window, tap on the + or - icon to change the number

Tap 'Set' and then 'Done' to save the changes.

Tap on the med via your 'Medication' list

Tap 'Edit'

Tap on 'Reminders'

Tap on the scheduled time/dose

Tap on the number where it says the number of pills and type in your desired half dose

Tap 'Done' then the back arrow

Tap 'Update' to save the changes
​