Is it possible to have a checkbox group with more than one fillable "Other" option?

i want the person to be able to check and fill in several boxes:

Allergies/Medications:____________________
Health Concerns:________________________
Other:____________________

thanks.

You may want to use the Configurable List widget instead. 

User guide: https://www.jotform.com/help/282-How-to-Set-Up-the-Configurable-List-Widget

Using the configurable list widget, you will be able to create custom mixed field type.

I.E. you can have both checkboxes and textboxes on the same field.

Hope this help. Let us know if you need further assistance.