A medical apparatus includes a storing section in which information concerning a drug movement in a living body is stored, an arithmetic processing section that acquires, based on the information stored in the storing section, information concerning a target region to which a first fluorescent drug is administered, information concerning a method of administering the first fluorescent drug, and information indicating start of administration, diagnosis end timing corresponding to the first fluorescent drug and sets, administration start timing of a second fluorescent drug, and a control section that performs control to start the administration of the second fluorescent drug when a current time reaches the administration start timing of the second fluorescent drug and, after the diagnosis end timing corresponding to the first fluorescent drug, performs control to reduce an irradiating light amount of excitation light for exciting the first fluorescent drug.