I need a doctor.
'Medico' — ME-di-co. Stress on the first syllable; hard 'c' before 'o'.
Say this in an emergency or when feeling unwell at a hotel, on a tour, or in a public place. Hotel staff can call a doctor who makes house visits (medico a domicilio).
'Ho bisogno di' (I need) + noun is the standard Italian need expression. It is more formal than 'mi serve' but equally natural. 'Un medico' (a doctor) — 'medico' is the professional; 'dottore' is the courtesy title used for anyone with a university degree.
Chiamate un'ambulanza!
Call an ambulance!
Emergency: the number is 118.
Mi sento molto male.
I feel very unwell.
Describe your condition to get appropriate help.
C'è un medico qui?
Is there a doctor here?
Ask in public spaces during a sudden emergency.
Italy's SSN (Servizio Sanitario Nazionale) provides emergency healthcare free to all, including tourists. EU citizens with an EHIC card pay nothing for treatment in public facilities. Non-EU visitors receive treatment but may be billed — travel insurance is strongly recommended.