Why are a cat's pupils constantly dilated? - briefly
A cat's pupils may remain dilated due to low light conditions, emotional arousal, or underlying health issues such as hypertension or neurological disorders.
Why are a cat's pupils constantly dilated? - in detail
A cat’s pupils are constantly dilated due to a combination of physiological, environmental, and emotional factors. Cats possess highly sensitive eyes adapted to low-light conditions, allowing them to hunt effectively during dawn, dusk, or nighttime. The dilation of their pupils, known as mydriasis, maximizes the amount of light entering the eye, enhancing their ability to see in dim environments. This adaptation is controlled by the autonomic nervous system, which adjusts the size of the pupils based on light levels. In bright conditions, a cat’s pupils contract into narrow slits to reduce light intake, while in darkness, they expand to capture as much light as possible.
However, persistent pupil dilation in cats can also indicate underlying health issues or emotional states. Certain medical conditions, such as hypertension, glaucoma, or neurological disorders, can cause prolonged dilation. Additionally, pain, stress, or anxiety may trigger the autonomic nervous system to keep the pupils enlarged. For example, a cat experiencing discomfort or fear may exhibit dilated pupils as part of its fight-or-flight response. Exposure to certain medications or toxins can also lead to abnormal pupil dilation.
It is essential to observe other behavioral and physical signs to determine the cause of persistent pupil dilation. If accompanied by symptoms like lethargy, changes in appetite, or unusual behavior, a veterinary consultation is recommended to rule out medical concerns. In healthy cats, dilated pupils are often a natural response to low light or heightened arousal, reflecting their evolutionary adaptation as nocturnal predators.