MONA is a mnemonic that was taught to medical professionals, such as doctors, nurses, and emergency medical technicians (EMTs), for the initial management of a suspected heart attack. It stands for:

  • morphine
  • oxygen therapy
  • nitrates
  • aspirin

MONA is no longer taught to new health professionals. Emerging research, including reviews of studies, suggests that MONA isn’t as effective as previously thought.

Of the four MONA treatments for heart attack, only aspirin is still routinely recommended by the American Heart Association (AHA) and the American College of Cardiology (ACC).

Read on to learn more about MONA, including why it’s no longer taught and what medical associations now recommend.

MONA was a mnemonic taught to emergency room personnel and EMTs for the initial treatment of acute coronary syndrome. Acute coronary syndrome is a group of conditions characterized by lack of blood flow to the heart. These conditions include:

  • Unstable angina: Unstable angina is characterized by reduced blood flow to your heart that puts you at risk of a heart attack.
  • ST-segment elevation myocardial infarction (STEMI): STEMI, or a classic heart attack, is caused by a complete obstruction of your coronary artery.
  • Non-ST segment elevation myocardial infarction (NSTEMI): NSTEMI is usually a less damaging type of heart attack caused by a partial obstruction of the coronary artery.

The goals of MONA were to:

  • reduce symptoms
  • prevent or limit heart damage
  • improve outcomes

The MONA mnemonic wasn’t intended to specify what order treatment should be administered but simply provided an easy way to remember the components.

MONA treatments

The four treatments that made up MONA include:

  • Morphine: Morphine is an opioid pain medication that’s given to reduce pain associated with a heart attack. Its use for heart attacks dates back to at least the 1930s.
  • Oxygen therapy: Oxygen therapy is when medical professionals give you extra oxygen through a mask or tube to increase oxygen levels in your blood. It has been used to treat heart attacks since about 1900.
  • Nitrates: Nitrates are medications that help relax your arteries to increase blood flow to your heart. Nitrates have been used to treat cardiovascular disease since the late 1800s.
  • Aspirin: Aspirin is administered after a heart attack to help thin your blood and reduce blood clots that may be contributing to a blockage. Aspirin’s blood-thinning effects have been recognized since the 1960s.
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Over the past 100 years, the risk of in-hospital death after a heart attack has decreased by about 90%. However, some parts of the MONA treatment may be associated with poorer outcomes.

For example, in a 2015 study, researchers compared the outcomes of people with STEMI (a classic heart attack), without low blood oxygen levels, who either received 8 liters per minute of oxygen or no oxygen. The researchers found that administering oxygen was associated with more heart damage at 6 months.

In a 2015 review of studies, researchers found evidence that the routine use of morphine, oxygen therapy, and nitrates isn’t supported. They concluded that MONA should be reconsidered as a teaching aid.

In a 2018 review, researchers concluded that MONA should be viewed as obsolete.

It’s now thought that strictly following MONA might do more harm than good because it doesn’t include the use of potentially beneficial drugs.

Of the four steps, only aspirin is still routinely recommended as an initial heart attack treatment by the AHA and ACC. The other treatments are still recommended in specific situations.

Here’s a summary of what research has found about each MONA treatment and the recommendations of the AHA and ACC:

TreatmentFindingsAHA/ACC recommendations
Morphine– No benefit for decreasing death rate
– Associated with higher death rate in people with NSTEMI
– Perhaps more heart damage in people with STEMI
– NSTEMI: moderate recommendation
– STEMI: drug of choice for pain relief
Oxygen therapy– No benefit for decreasing death rate
– Associated with higher risk of recurrent heart attack or major arrhythmias
– NSTEMI: strongly recommended when oxygen saturation is under 90%
– STEMI: may be used if oxygen saturation is under 90%
Nitrates– No benefit for decreasing death rate– NSTEMI: strongly recommended for persistent lack of blood flow (ischemia), heart failure, or high blood pressure
Aspirin– Associated with improved death rate– Strongly recommended for NSTEMI and STEMI

The AHA and ACC still strongly recommend the use of aspirin in initial heart attack treatment, except for anyone who’s not able to take it safely.

Many different medications are under investigation for the initial treatment of heart attacks.


In a 2015 study, researchers proposed a new mnemonic, known as THROMBINS2, to include a wider range of current treatment options, which includes:

This expanded list of treatments is now part of current heart attack management.

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The Centers for Disease Control and Prevention recommends calling 911 or local emergency services immediately if you or somebody you’re with develops symptoms of a heart attack. The primary symptoms include:

After calling 911, the Red Cross recommends:

  • being prepared to administer CPR or an automated external defibrillator if the person stops breathing and becomes unresponsive
  • helping the person into a comfortable position and loosening tight clothing
  • getting the person’s medication if they have medication prescribed for chest pain
  • reassuring and monitoring them until the ambulance arrives
  • offering aspirin if the person is responsive, able to chew, and doesn’t have a medical condition that prevents them from receiving aspirin safely

MONA is a mnemonic that used to be taught to new medical professionals to help them memorize how to treat heart attacks. New research has made MONA outdated, however. Of the four MONA treatments, current guidelines only recommend routine administration of aspirin. The other three treatments are still administered in specific situations.

It’s important to call 911 any time you suspect you or somebody you’re with is having a heart attack. The sooner treatment is started, the lower the chances of having severe complications.