The reqirements depends on the type of visa issued.

if its a Residency Visit Visa / Family Residence Visa there he will need to get the medical check. This medical is called Medical Clearance and its from accredited clinics.

Here is the link to the requirements: http://qatarembassy.com.ph/index.php/consular-service/visa

Accredited Clinics:
http://qatarembassy.com.ph/index.php/consular-service/accredited-medical...

My company issued a Res Visit Visa / Family Res Visa for my wife. She just done the medical and sent it through DHL (wwwexpress). They required her to submit an english version of the visa. This can be done at the MOI web site http://www.moi.gov.qa/site/english/eServices/index.html

Good Luck