What is the SOS drug for chest pain?

Q: If someone at home (age 50+) complains of chest pain (for the first time) and one is not sure if it is a heart attack, what is the best medicine to give immediately i.e. before calling the doctor-aspirin, isosorbide dinitrate, nimulid etc. (please specify)? If it is not a heart attack, would giving isosorbide dinitrate cause any problems?

A:If the diagnosis is not confirmed, and there are no contraindications (asthma, peptic ulcer) then aspirin is the best option.