Home healthcare in the UAE is a licensed activity twice over: the doctor holds a personal professional licence, and the company holds a facility licence for home healthcare services. The authority depends on the emirate where the service operates. In Dubai it is the Dubai Health Authority, and you can check any practitioner on the DHA's public licence search. In Abu Dhabi and Al Ain it is the Department of Health, with its own professional register. Sharjah, Ajman, Ras Al Khaimah, Fujairah and Umm Al Quwain fall under the Ministry of Health and Prevention, MOHAP, which also runs a searchable registry.
Verification takes two minutes and is worth doing once per vendor rather than per visit: ask for the doctor's name and licence number when the booking is confirmed, and check it against the relevant register. A legitimate operation will send this without friction; hesitation is information. Cross-border wrinkle: a Dubai-licensed doctor visiting you in Sharjah should be working under an arrangement licensed for that emirate, which is one reason marketplace platforms that verify vendor licensing before listing them, tamam does this across its health categories, save you the homework.