Does diabetes qualify as disabled?

If I have diabetes and am regarded by the company as a person with disabilities, in my tax return can I say I am disabled?

Why are you regarded as being disabled by your company?

I am regarded as a person on long term treatment.

You would need to complete a form called a ITR-DD and have that submitted to SARS for them to approve with all the supporting documentation. You would then, on acceptance, have this valid for 5 years and be able to deduct medical expenses in accordance with the rules allowed for disability.