My sweet baby boy is 10 weeks old. I just thought I would post remedies my pediatrician recommended when my son was dealing with diaper rash and constipation.
For constipation: 1oz of apple juice every 24hrs until you see improvement
As long as your child is older than 1 mo you can use this method to help alleviate constipation.
For diaper rash: equal parts aquaphor and maalox. Mix together and apply to rash. This mixture worked like a charm when no over the counter diaper rash cream would.