You can enter these expenses in TurboTax Online here:
Navigate to Federal > Deductions & Credits > Medical Expenses > Start or Edit
Enter all the expenses you have as you go through the categories
On the screen "Tell us about any other medical expenses" you can enter the cost of the supplements
Note that in order to claim medical expenses you must itemize deductions and only the expenses over 7.5% of your AGI are deductible.
If you are unable to get to the medical expense entry after following these steps, I would suggest clearing your cookies and cache to start (How to clear your cache).
TurboTax Expert Assist
Get answers to all your tax questions
Our experts are available on-demand, no appointment needed. Get help all year long with TurboTax Expert Assist.