Please note of the latest news is that business visas (3 months) and tourist visas (28 days) can no longer be extended.
Exit has to be back to the country of origin (based on passport)

As to your question, for business visa (even visit visa) medical exam is no longer required. However, it has to be authenticated by Qatar Embassy in Manila. It takes one week to have the visa authenticated. You have to send it via DHL. (BTW, not all DHL outlets have the visa authentication service) Business / visit visas also require a return ticket. One-way ticket is not accepted.