cat acting weird after being outdoors
Behavioral Problems

Why Is My Cat Acting Strange After Being Outside?

Exploring outdoors can be dangerous for cats. Perhaps your cat will return home acting oddly due to a negative experience.

Your cat may be acting strangely after being outside because it’s been attacked by another animal, got lost, or hurt itself. Ensure that your cat has not consumed poisons or contracted a disease. An unspayed cat could return pregnant, which will lead to personality changes.

Some cats will always want to roam outside. If your cat returns from wandering with a much-changed personality, it’s best to keep it indoors.

Why Is My Cat Acting Weird After Spending Time Outdoors?

If your cat returns from time outside behaving differently, it is possible that your cat has experienced trauma. Common mishaps include:

  • Conflict with a neighborhood cat
  • Wild animal attacks
  • Catching a contagious disease
  • Parasite infestation
  • Injury
  • Consumption of toxins
  • Loss of bearings
  • Pregnancy

Any of these experiences will traumatize a cat, leaving your cat jumpy and apprehensive.

Conflict with a Rival Cat

Cats are territorial by nature. This means that cats will often come into conflict when they encounter each other. Your cat wandering into a neighbor’s property will be seen as an invasion.

When two cats come into conflict, they will often try to avoid fighting. Both cats will make themselves look as big as possible. They will attempt to frighten the other cat away.

cat behaving strangely

Sometimes, this approach works. Your cat may have been spooked by another feline, though. This makes the cat feel uncomfortable venturing outside. Your cat will become anxious at the idea of encountering the other cat again.

If both cats are dominant, conflict becomes likely. Neither will wish to back down. That is seen as a sign of weakness. In such cases, physical conflict becomes inevitable. This will be traumatic for your cat, whether it wins or loses the fight.

Cat fights are not calm or sedate. If a cat feels that it needs to fight, it will fight for its life. Claws and teeth will be used, targeting painful, delicate parts of the other cat’s anatomy. Even if your cat is not injured, it will be shaken by the experience.

In addition, cats have long memories when wronged. Your cat will remember the cat that it came into conflict with. This will generate further conflict in the future. Acting in fear, the cat will become aggressive upon sighting this enemy.

Keep your cat indoors and offer plenty of reassurance. Keep your cat in a strict, reliable routine. Your cat needs to know that the home environment is safe. The cat will decide if and when it wishes to wander outside again.

Animal Attacks

Neighborhood cats are not the only animal danger to a domesticated feline. Some breeds of dogs have high prey drives and instinctively chase cats.

Outside of domesticated pets, wild animals can frighten or attack a cat. Depending on where you live, your cat could encounter the following:

Just like cats, these animals will act on instinct. If it feels threatened, even something as seemingly innocuous as a squirrel can bite. Like cats, many wild animals consider attack to the best form of defense.

Your cat may antagonize these animals. If your cat feels a wild animal has invaded its territory, it may behave with aggression.

Fights between cats and wild animals, including feral cats, must be avoided if possible. In addition to the risk of injury, some wild animals carry disease and parasites.

Contagious Diseases and Infections

One of the most compelling arguments for keeping a cat indoors is the risk of contagious disease. You can reduce the risk of disease through vaccination. Vaccinations are not a cure-all, though. In some cases, they merely minimize symptoms, not prevent exposure.

As Nature explains, Feline Leukemia Virus (FeLV) is commonly spread by cat-on-cat interaction. FeLV is just one contagious disease that cats can catch from animals. Other bacterial or fungal infections passed between mammals include:

  • Feline Panleukopenia (FP, aka Feline Distemper)
  • Feline Herpesvirus (FHV)
  • Feline Calicivirus (FCV)
  • Feline Immunodeficiency Virus (FIV)
  • Bordetella bronchiseptica (B. bronchiseptica)

These ailments will be comparatively simple to spot. Symptoms will manifest as upper respiratory infections. Your cat will experience:

  • Streaming eyes and nose
  • Loss of appetite
  • Lethargy
  • Fever
  • Drooling
  • Coughing

Upper respiratory infections are treated with antibiotics and plenty of rest. Your cat must stay home until it is no longer contagious. Leave the cat alone in a quiet room to recover.

Another risk to be aware of is ringworm. It is a fungal disease that will affect your cat’s skin and cause significant distress. Your cat’s skin will itch and be covered with spherical markings.

Ringworm is treated with topical anti-fungal lotion but is contagious to cats. If your cat caught ringworm, it must be quarantined until fully recovered.


Stray or feral cats do not receive flea treatments. Ticks can also feed on other animals before attaching themselves to cats.

This is problematic, for two reasons. The obvious issue is the discomfort that your cat will experience. Fleas and ticks bite and make a cat’s skin itch. The cat will be in some distress as it attempts to relieve these symptoms.

As Frontiers in Bioscience explains, ticks can also be disease carriers. If a tick feeds on infected blood, it can pass on the disease to a cat. Some of the significant, and potentially lethal, infections passed on by ticks include:

  • Ehrlichiosis
  • Lyme Disease
  • Tularemia (aka Rabbit Fever)
  • Rocky Mountain Spotted Fever (RMSF)

Always check your cat for parasites when it wanders outside.


Cats often hide pain and injury. Scratches and cuts from conflict will be obvious, due to bleeding. Muscular strains, aches, and even broken limbs can be harder to immediately identify.

Cats do not like to reveal pain as it could result in being forced to concede territory. Your cat may avoid moving at all so you do not see it limping.

There are other ways to identify pain in animals. Symptoms include:

  • Meowing and verbalizing constantly
  • Uncharacteristic aggression
  • Refusing any kind of handling
  • Excessive grooming

If you suspect that your cat is injured, investigate if you can. Remember, a cat will not let you touch it if in discomfort.


Many cats love to climb. Your cat may have attempted to scale a fence or climb a tree. Sometimes, the cat gets stuck. This could lead to an accidental fall, or a jump from height born of desperation.

Progress in Brain Research explains how there is some truth to the idiom that cats land on their feet. Cats instinctively reshape their bodies when falling, minimizing impact upon landing.

Muscular injuries or bone fractures are possible, though.

Road Traffic Accidents

A road traffic accident involving a cat is every owner’s worst nightmare. If you live close to fast-moving traffic, this is always a risk. As the Journal of Small Animal Practice explains, road traffic accidents often lead to injury.

According to Veterinary Record, cats in rural territories experience more accidents than urban territories. This is due to the speed that vehicles move in such locations. A lack of constant exposure to traffic also reduces a cat’s awareness of the danger.

Senior cats are the least likely to experience a road traffic accident. As cats age, they develop more road sense.

Muscle Injuries

Cats spend the majority of their day sleeping for good reason. When a cat hunts, it uses a great deal of energy. The cat will pounce and stretch on instinct, ensuring that even the fastest prey cannot escape.

Unfortunately, a cat’s body may not be ready for this much activity at once. Cats can experience muscle strains and tears through rapid activity. If a cat launches itself at prey without warming up first, minor injury is possible.

Minor strains will typically heal themselves in a day or two. Ensure your cat is comfortable. Plenty of rest will speed up the recovery process.


Toxins are a constant risk for a wandering cat. Blocking exposure to toxins in the home is comparatively simple. You can remove access to cleaning products, or dangerous foods such as chocolate.

Outside, there are three primary sources of toxicity to a wandering cat:

  • Consumption of toxic plants
  • Consumption of toxic prey animals
  • Toxic stings or bites from insects

Your cat may encounter any of these issues. Examples of toxic plants that are native to the United States include:

  • Lilies
  • Larkspur
  • Dumbcane
  • Foxglove
  • Castor bean
  • Oleander
  • Black Locust
  • Autumn Crocus
  • Caladium
  • Sago Palm

Cats with high hunting drives may also consume toxins by proxy. A cat hunting a mouse that recently ate rodent poison, for example, will be at risk. Slugs and snails are also toxic to cats. If the slug recently ate poisoned pellets, this danger is magnified.

Finally, consider if your cat was attacked or bitten by an insect, spider or snake. This impact of this varies. Your cat may feel a little sorry for itself then bounce back as the pain subsides. Alternatively, the cat may display signs of dangerous toxicity, such as:

  • Pale gums
  • Drooling and frothing at the mouth
  • A drop in body temperature
  • Muscular weakness and tremors
  • Visible swelling
cat aggressive after being outside

Getting Lost

Sometimes, a cat will accidentally find itself far from home. The cat may have been frightened by a loud noise and fled. Some cats stalk prey over a prolonged distance. The cat loses itself in the thrill of the hunt. When the hunt is complete, the cat is unfamiliar terrain.

Most cats will not venture further than 100 meters from home. Unfixed male cats may wander further, seeking a potential mate. As a rule, cats stay close to home. This allows the cat to seek out familiar terrain using scent.

If a cat finds itself lost, it can become distressing. Getting lost means the cat will miss out on structured meals and playtimes. The cat may also grow anxious at lacking a reliable source of food or water. Hostility from local animals is also likely.

While lost cats often return home eventually, the experience can be psychologically scarring. The cat will be clingy and needy for a while. Provide the cat with the reassurance it needs.


An unspayed female cat is fertile throughout her life. If the cat is in estrus, she will be desperate to get outside.

Once in the open, her hormones will attract every intact tom in the area. It’s rare for a cat in heat to return home without being impregnated.

A pregnant cat will display changed behaviors, including:

  • Increased affection and clinginess
  • Enhanced appetite
  • Sleeping for longer, and more often
  • Vomiting in the morning

Naturally, your cat will also steadily gain weight. Her nipples will also swell in size and become more prominent. This is known as ‘pinking up.’

If your cat is pregnant, she is less likely to show interest in going outside. In fact, she may become outright hostile to male cats that approach her. It’s safer to keep your cat indoors, focusing on her comfort.

The outdoors can provide a range of exciting stimulation for cats. It is also fraught with danger, though. Many cats start to behave strangely after being outside. This suggests that something occurred to upset your cat.

If your outdoor cat is behaving in a strange way, then it’s likely had a bad experience. A sudden change in demeanor must be investigated.