While my husband was ill and on long term disability, we had to send a check each month to his employer for his insurance premium. Can I claim those premiums?

Yes, you can include the insurance  premiums as medical expenses. 

Please keep in mind the following about deducting your medical expenses, including insurance premiums:

• You don't get the benefit if you are taking the standard deduction.
• If you itemize deductions, you will only be able to take total medical expenses that are greater than 7.5% of your adjusted gross income.

To enter your medical expenses in TurboTax, please follow these steps:

1. Click on Federal Taxes > Deductions & Credits 
2. In the Medical section, click on the Start/Revisit box next to Medical Expenses.
3. If you haven't yet entered any medical expenses, TurboTax will ask you if your total medical expenses exceed a certain number.  [That's the 7.5% AGI mentioned above.]      
   
4. If you think your total medical expenses will exceed that number, click the blue Yes box and continue through the interview, entering the requested information on your medical expenses, including insurance premiums.