Brachycephalic Pets and BOAS: What You Need to Know Before You Travel

Brachycephalic pets — pugs, French Bulldogs, English Bulldogs, Persian cats, and their relatives — are some of the most popular animals we help relocate, and also some of the most fragile once a crate door closes. Their signature flattened muzzle isn’t just a look; it’s a structural airway problem with a name: Brachycephalic Obstructive Airway Syndrome, or BOAS. If you’re planning to move with a snub-nosed pet, understanding BOAS should shape every decision about how, and whether, your pet travels.

What Is BOAS, and Which Breeds Are Most at Risk

BOAS comes from the shortened skull shape bred into certain dog and cat breeds. Narrowed nostrils, an elongated soft palate, and a smaller windpipe combine to make normal breathing more physically demanding, even at rest. Add exercise, heat, stress, or altitude, and an already-compromised airway can struggle to keep up.

Breeds most commonly affected include:

• Dogs: French Bulldogs, English Bulldogs, Pugs, Boston Terriers, Boxers, Shih Tzus, Pekingese, and Cavalier King Charles Spaniels
• Cats: Persians, Himalayans, Exotic Shorthairs, and Burmese

Severity varies a lot within a breed. Some individual pets have mild anatomy and travel fine; others are compromised enough that even a warm afternoon indoors is a struggle.

Why Air Travel Raises the Stakes

The cargo hold of an aircraft is a uniquely bad environment for a compromised airway: lower oxygen levels, temperature swings on the tarmac, and the stress of confinement all place extra demand on lungs that are already working overtime. Because of this, most major airlines, including Delta, American, and Austrian Airlines, have stopped accepting brachycephalic breeds in cargo altogether, and several others impose strict temperature and seasonal restrictions even for approved pets.

Cabin travel in an under-seat carrier is generally the safer option when a pet is small enough to qualify, since they stay in a climate-controlled space with you rather than in the hold. IATA’s Live Animal Regulations also require a container at least 10% larger than standard sizing for snub-nosed breeds, to ease airflow around the animal.

Start With a Fit-to-Fly Veterinary Assessment

Not every flat-faced pet carries the same level of risk, which is why a guess isn’t good enough. A pre-travel veterinary exam, ideally using a structured brachycephalic fit-to-fly assessment like the one IPATA-certified vets use, gives you an honest answer. Your vet should evaluate airway function, weight, and general fitness for travel, and flag any pet that should stay grounded or travel only by climate-controlled ground transport.

Why We Often Recommend Ground Transport

For many of the BOAS breeds we work with, a climate-controlled ground vehicle is simply the safer call, especially in a tropical climate like the Philippines, where heat and humidity compound an already-narrow airway. Ground transport lets us control temperature precisely, make stops to check on your pet, and avoid the pressure and oxygen changes of a flight entirely. It takes longer than flying, but for a dog or cat with a genuinely fragile airway, that trade-off is usually worth it.

If Your Pet Is Cleared to Fly, Do These Things

• Book a direct flight to avoid layover delays sitting on the tarmac
• Travel during the coolest part of the day, and avoid peak summer heat if you can reschedule
• Use a carrier at least 10% larger than standard sizing to ease airflow
• Never sedate a brachycephalic pet for travel — sedatives suppress breathing and are specifically discouraged by veterinary associations for this reason
• Keep your pet calm and hydrated in the hours before departure
• Work with a transport provider experienced in brachycephalic-specific handling

Not sure whether your pet is a safe candidate for flying? Talk to PetTransPRO before you book anything — we’ll walk through your pet’s breed, age, and health history and help you choose the option that actually keeps them safe, not just the fastest one.