It is late, the prep is not doing what the leaflet said, and there is nobody to ask. These are the common ones.
Call the number on your prep instructions. Out of hours that sheet usually gives an on-call line, and an endoscopy unit would far rather answer this at 10pm than have you arrive unprepared.
Stop and call. Whether to wait and restart, slow the rate, or use something for the nausea depends on how much stayed down and how far in you are, and pushing on regardless is how people end up either sick or unprepared.
Call before you give up on the rest. Finishing matters more than most people realize, and there are usually options, chilling it, a straw, a chaser between glasses, or a different plan for the second dose.
For most kits the first dose takes one to three hours, and it is normal for nothing to happen for a while. If you are well past that with no movement at all, call rather than take anything extra on your own.
Say so when you check in, and call ahead if there is time. Arriving without saying it is the thing that leads to a repeat, and they can sometimes give you more prep or move your slot.
Call. Do not double up to catch up. The gap between the last dose and your check-in is part of how the timing works, so this is a question about your specific appointment.
Chills, a headache, feeling wiped out, some nausea, cramping in waves, a sore backside, and being awake far later than you wanted. Unpleasant, and expected. What is not routine is severe or worsening belly pain, vomiting you cannot stop, or feeling faint. Those are worth the phone call.
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