How alcohol affects your eyes

One of the most immediate and noticeable effects of alcohol on our vision is blurry or distorted sight. This effect is due to the impact alcohol has on the brain and its communication with the eyes. Specifically, alcohol inhibits the neurotransmitters in our brains, slowing their pace and affecting how our brains process what we see.
Neurotransmitters are chemical messengers that transmit signals throughout the body to trigger various physiological responses. When alcohol enters the system, it suppresses these messengers, causing delays and disruptions in signal transmission. As a result, the instructions sent from the brain to the eye muscles and the pupil become less precise and slower, leading to difficulty focusing. This causes blurred or double vision commonly associated with alcohol consumption.

Another significant short-term effect of alcohol on eyesight is a reduction in peripheral vision, often called tunnel vision. This means that while your central vision remains relatively clear, your side (or peripheral) vision becomes increasingly blurry or distorted, creating a tunnel-like effect.
Again, this is down to how alcohol impairs the brain's ability to process visual signals. The retina—the light-sensitive layer at the back of the eye—sends signals about what we see to the brain, where these signals are processed into images. When alcohol is consumed, the brain's ability to interpret these signals effectively is compromised, particularly in the peripheral areas of our visual field.

Alcohol also causes physical changes to the eyes themselves. One of the most common short-term effects of alcohol consumption is bloodshot or red eyes. This is because alcohol causes blood vessels—including those in the eyes—to expand, a condition known as vasodilation.
When the blood vessels in the whites of our eyes dilate, they become more visible, giving the eyes a reddish appearance. While this is generally temporary and resolves as the alcohol is metabolised and removed from the body, frequent occurrences can lead to the blood vessels in the eyes being permanently damaged, leading to persistently red eyes.
Eye sprays and drops may be helpful, as well as some home remedies like placing a cold compress, or a spoon, which creates a drop in temperature on the eye surface, helping restrict the blood vessels and reduce the redness.

Alcohol is a diuretic, causing your body to remove fluids faster and giving you dry eyes. This dehydration extends to your eyes, accelerating the symptoms of dry eye syndrome (itchiness, a burning sensation, blurry vision, watery eyes etc.). Try to replace lost fluid with glasses of water. A rough guide is 1 large glass of water per 2 units of alcohol drunk. Also, remember to remove your contact lenses before going to bed, as they limit the amount of oxygen reaching your cornea - and may lead to long-term conditions like keratitis (inflammation of the cornea). Using an eye spray or eye drops is also recommended to give a boost of moisture.

Eyelid twitching is another indicator of (excessive) alcohol consumption. This painless, but annoying eye spasm is also known as myokymia. The twitching sensation should go away within a few days. If it lasts longer than 2 weeks, you should see a doctor. If you find your eyelids twitch on a regular basis, it may be because of stress, lack of sleep, too much caffeine or a vitamin deficiency.

Alcohol causes your body to dehydrate, which in turn causes your organs (which includes your skin) to 'fight back' by retaining water - which may lead to bags under eyes.

Alcohol can slow the reaction time of your pupils, making them less responsive to changes in light. This can result in increased sensitivity to light and difficulties adjusting from dark to bright environments.

This is a quite common. It’s a symptom of dry eyes and dry eye disease for some people. The diuretic effects of alcohol cause your body to remove water (through your urine) at a higher rate. This dehydrates your eyes, accelerating the symptoms of dry eye syndrome (which include itchiness, a burning sensation, blurry vision, and for some people, watery eyes).

One of the most common eye conditions associated with heavy drinking over a prolonged period is the development of Cataracts. Cataracts involve the clouding of the eye's lens, which sits behind the iris and pupil. This clouding can interfere with the quality of the light that reaches the retina, leading to blurry or foggy vision and, if left untreated, blindness.
The link between alcohol and cataracts isn't entirely understood. Still, research suggests heavy drinking might contribute to cataracts' onset and progression. One reason might be the nutritional deficiencies commonly seen in people with chronic alcohol use, as nutrients like vitamins C and E and antioxidants are crucial for eye health.

Long-term alcohol use is also linked to an increased risk of Age-related Macular Degeneration (AMD). This condition affects the macula, the part of the retina responsible for sharp, central vision. Over time, AMD can lead to a loss of central vision, impacting activities like reading, driving, and recognizing faces.
Again, the precise relationship between alcohol and AMD is not entirely clear. However, it's thought that alcohol's toxic effects, combined with malnutrition often seen in chronic alcoholics, could contribute to damage in the macula, leading to AMD.

Another severe eye condition related to chronic alcohol use is optic neuropathy, sometimes called tobacco-alcohol amblyopia. This condition involves damage to the optic nerve, the bundle of nerve fibres that transmit visual information from your eyes to your brain. When these fibres are damaged, the transmission of visual information is disrupted, leading to vision loss.
Alcohol-induced optic neuropathy is often associated with poor dietary habits common in alcoholism. Deficiencies in particular nutrients, especially B vitamins, can harm the optic nerve. Moreover, the toxic effect of alcohol itself may directly damage this crucial nerve.

Chronic alcohol consumption can lead to persistent dry eyes due to its diuretic effect. Over time, this chronic dryness can damage the cornea and lead to discomfort and vision problems.

This condition involves changes to the vitreous humour, the gel-like substance inside the eye. Alcohol, especially when consumed heavily, may contribute to this degeneration, leading to floaters, flashes, and potentially more serious eye conditions.

Chronic alcohol use can impair the ability to differentiate between different colours, especially shades of blue and green.

Also known as amblyopia. A lazy eye can stem from excessive drinking, which increases your risk of vision loss and/or permanent damage.

Vitamins are essential for eye function. Heavy drinking drains your body's natural reserves - which may result in optic neuritis. This condition inflames the optic nerve, leading to loss of central vision and blurry vision.

In terms of eye-related symptoms, one common issue people might experience during alcohol withdrawal is hypersensitivity to light, a condition known as photophobia. Being in brightly lit environments can make it uncomfortable or even painful.

Visual hallucinations are another symptom that can occur during alcohol withdrawal. These hallucinations can be very distressing and may involve seeing non-existent patterns, objects, or lights.

In extreme cases, prolonged alcohol abuse and subsequent withdrawal can lead to severe conditions such as optic neuropathy and optic atrophy. Optic neuropathy refers to damage to the optic nerve, which can cause vision loss. Optic atrophy is a condition characterized by the degeneration of optic nerve fibres, which can potentially result in blindness.