The pupil is a hole in the centre of the iris. This hole allows the light to enter the eye and reach the retina. Normal reaction of the pupil is dilatation and constriction. If there is too much light the pupils constrict while in the presence of insufficient light or complete darkness the pupils dilate. The reaction in these cases includes both pupils. However, there are certain medical conditions which may cause pathological dilatation of pupils.
Causes of Dilated Pupils
Doctors can easily notice dilatation of pupils. Even people may notice widening of these holes just by looking in the mirror. Dilatation is usually a normal process but it may also point to the presence of some underlying condition, be related to certain medications and this is why pupil dilatation in some cases requires further examination.
The most common cause of dilated pupils is exposure to darkness and lack of the light. As it has been already mentioned, in case of insufficient amount of the light pupils dilate and this way they increase the entrance of the light. So dilatation of the pupils in the dark or reduced light is normal and does not require any additional examination.
Apart from their normal reaction pupils can dilate due to intake of certain drugs and medications. This is usually a side effect of either prescribed or over-the-counter medications. These medications are discontinued and the doctor prescribes other medications that do not lead to pupil dilatation. Pupil dilatation can additionally occur due to specific eye drops commonly used by ophthalmologists during eye examination. Dilatation is in this case artificially induced to help the doctor examine all the parts of the eye, particularly the retina. However, dilatation of the pupils can be caused by certain illegal drugs and narcotics. They include marijuana, cocaine, crystal meth, ecstasy, certain mushrooms, and LSD.
Another cause of dilated pupils is poisoning. Exposure to certain biological or chemical poisons may result in pupil dilatation. If people who have been poisoned have dilated pupils this is not a good sign since pupil dilatation in this case points to serious poisoning. The doctors need to act promptly and try to eliminate the toxin from the body as soon as possible.
Certain studies have connected sexual arousal with specific changes in central nervous system. To be more precise, when a person is sexually aroused or in case that he/ she noticed someone attractive the central nervous system sends numerous signals causing specific effects. Dilatation of pupils is only one of the body's reactions to the previously mentioned situations.