The addendum is one of the most misused tools in a medical school application. Applicants either skip it when they should write one, or write lengthy justifications for things that do not need explaining.

An addendum is a brief, factual explanation of a specific anomaly in your record — something that a reader would otherwise interpret negatively without context.

When You Should Write an Addendum

Academic performance anomalies: A semester or year of significantly lower grades due to a documented illness, a family emergency, or a mental health crisis.

Late diagnosis of a learning disability or mental health condition: If you were diagnosed with ADHD, dyslexia, or a similar condition during college, explaining the diagnosis and how you have since managed it is appropriate.

MCAT score outlier: If one of your MCAT scores is significantly lower than your others, and there is a specific reason (documented illness on test day, a personal crisis), a brief addendum clarifies it.

Institutional action or disciplinary record: AMCAS asks directly whether you have ever been subject to institutional action. If the answer is yes, you must address it.

Gap in education or unusual timeline: If there is a multi-year gap not otherwise explained — military service, illness, caregiving responsibilities — a brief addendum provides context.

When You Should Not Write an Addendum

  • A single bad grade in a course that was not part of a larger pattern
  • A low GPA that reflects consistent academic performance rather than a specific event
  • An MCAT score you simply wish were higher
  • Anything you are explaining out of insecurity rather than because a reader would actually be confused

Understand where your GPA and MCAT stand before you apply

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What a Good Addendum Looks Like

The structure is: fact, context, resolution. What happened, why it happened, and what changed.

  • Keep it brief: 150–250 words is almost always sufficient.
  • Be factual, not emotional: Do not ask for sympathy. State what happened and explain the context.
  • Be forward-looking: End with who you are now, not who you were then.
  • Do not over-explain: A single clear paragraph is better than a page of justification.
  • Avoid blame: Blaming professors, family members, or circumstances reads badly. Own your record and explain it.

The Disciplinary Action Addendum

This is the highest-stakes addendum category. Medical schools are training professionals who will be entrusted with patient lives. Any institutional action will be scrutinized carefully.

If you have a disciplinary record, disclose it fully and accurately. Inconsistencies between your self-disclosure and what schools discover independently are far more damaging than the original incident.

The effective approach: state what happened factually, take responsibility clearly, explain the context without minimizing your role, describe what you learned, and explain what has changed since.

Where to Submit Addenda

AMCAS does not have a dedicated addendum field. Addenda are typically submitted as additional essays on secondary applications. Some schools ask directly whether there is anything else they should know about your record — this is the natural home for an addendum.

Write the addendum once, refine it carefully, and use it consistently. It should read like a considered statement, not something you wrote in response to anxiety.