"Is my baby drinking less since the dose of Nexium was increased?"

It is possible that the decrease in drinking could be due to the increase in the dose of Nexium, especially if the increase was made because your baby was still experiencing symptoms. It is important to monitor your baby's overall condition and as long as they are still eating and drinking, there may be no cause for concern. It is common for children to be irritable for a longer period of time after an illness or vaccination. Just keep an eye on their general well-being and if you notice any significant changes, it may be worth consulting with a healthcare professional.