You can call an ambulance in the event of an emergency, but taxis are often faster. For car accidents, call the city police.
Ambulance. City Police. Coast Guard. Fire. Tourist Police.
Most hotels will call a doctor or dentist for you; you can also contact your embassy for referrals to either. For a doctor on call 2 PM-7 AM on Sunday and holidays, dial 105 (in Greek).
Dial 106 (in Greek), check the Athens News or the English-language Kathimerini, or ask your hotel to check the Greek papers to find out which emergency hospitals are open; not all hospitals are open nightly. Hygeia Hospital is considered one of the best in Greece, as is its sister maternity hospital, Mitera; both have some English-speaking staff. Children go to Aglaia Kyriakou Hospital or Ayia Sofia Hospital. Note that children's hospitals answer the phone with "Pedon" and not the specific name of the institution.
Aglaia Kyriakou Hospital. Asklepion Hospital. Ayia Sofia Hospital. Hygeia Hospital. KAT Hospital. Mitera. Ygeia.
There are no 24-hour pharmacies in Athens; a Greek-language phone recording (dial 107) lists pharmacies open on holidays and late at night, or you can check the listings in the English-language Athens News or Kathimerini. Each pharmacy posts in its window (in Greek) a list of establishments close by that are open during the afternoon break or late at night. Many pharmacies in the center have someone who speaks English, or try Thomas, near the Hilton, for convenience and spoken English.
Late-night pharmacy hotline (in Greek). Thomas.