Part 67 Series — Substance Use, Diabetes & “Established Medical History”: What the FAA Is Really Looking For

When most private pilots think about FAA medical certification, they picture dramatic conditions:

Heart attacks.
Seizures.
Major psychiatric diagnoses.

But in reality, many medical deferrals don’t start with dramatic events.

They start with everyday health issues:

• High blood pressure

• Type 2 diabetes

• A prescription for anxiety medication

• A past DUI

• A history of alcohol dependence

Under FAR Part 67, the FAA doesn’t just evaluate catastrophic medical events. It also evaluates ongoing health conditions and substance-related history that could affect safe operation of a small aircraft.

In this fourth article of our five-part Part 67 series, we’ll break down:

• Substance abuse vs. substance dependence

• Alcohol- and drug-related standards

• Diabetes and metabolic disorders

• The meaning of “established medical history or clinical diagnosis”

Because sometimes it’s the common conditions — not the rare ones — that raise the most questions.

Let’s take a clear-eyed look at what the regulations actually say.

Substance Use & General Medical Conditions Under §67.303

For private pilots operating under a Third-Class medical certificate, the relevant standards are found in:

• §67.303 — Third-Class medical standards

This section includes language addressing:

• Substance abuse

• Substance dependence

• Certain personality and psychiatric disorders

• Other general medical conditions that may impair safe performance

Substance Abuse vs. Substance Dependence

The FAA distinguishes between:

Substance Abuse

Typically involves:

• Use of a substance in a situation that is physically hazardous,

• Or use resulting in legal, social, or occupational consequences.

Substance Dependence

Involves:

• Tolerance,

• Withdrawal symptoms,

• Impaired control over use,

• Continued use despite harm.

Under Part 67, a history of substance dependence is specifically disqualifying unless resolved and evaluated under FAA standards.

Substance abuse may also be disqualifying, particularly if recent or recurrent.

The FAA is evaluating risk — especially the risk of impaired judgment or relapse.

Alcohol-Related Motor Vehicle Actions

While Part 67 addresses medical standards, alcohol-related legal events (such as DUIs) often trigger FAA review.

The FAA evaluates:

• Blood alcohol concentration at the time of arrest

• Recurrence

• Evidence of dependence

• Compliance with treatment

A single event does not automatically end a flying career — but it almost always requires additional documentation and review.

Honest reporting is essential.

Diabetes & Metabolic Conditions

Historically, insulin-treated diabetes was disqualifying. Today, the FAA allows certification under structured evaluation pathways.

For Third-Class medical certification:

• Non-insulin-treated diabetes may be certifiable if controlled.

• Insulin-treated diabetes may qualify under special issuance with strict monitoring.

The FAA is concerned with:

• Risk of hypoglycemia (low blood sugar),

• Sudden cognitive impairment,

• Long-term complications.

Stable management and documentation are key.

“Established Medical History or Clinical Diagnosis”

You’ll see this phrase repeatedly in Part 67.

It means:

The FAA evaluates not only current symptoms, but also documented history.

Even if a condition is currently asymptomatic, the FAA may review:

• Past diagnoses,

• Treatment history,

• Medication use,

• Recurrence patterns.

This is why thorough and accurate disclosure on MedXPress is critical.

At this level, you now understand how Part 67 addresses common, ongoing health conditions.

But the deeper application of these standards often raises practical questions.