Methamphetamine is a very potent stimulant drug. It’s highly addictive and can have many harmful effects on the mind and body when used in the short and long term.
One of the most common physical characteristics of meth use and abuse is what’s called “meth eyes.” When someone is high on meth, their eyes will have a distinct appearance. That consists of:
- Dilated pupils
- Rapid eye movement
- A sharp and intense gaze
Meth’s effects that speed up the central nervous system are the primary reason why these meth eye symptoms occur. It essentially triggers your body’s fight-or-flight response system, which causes a big adrenaline rush and hormonal release.
There’s a lot more to unpack here about why meth eye effects occur and how they impact long-term ocular health. Read on as we discuss all the details.
Short-Term Ocular Effects
As mentioned, meth eyes can occur immediately after taking the drug. It’s a common bodily reaction and a sign that someone’s high on meth.
In the short term, no matter how you take the drug (smoking, injecting, snorting, or swallowing), it will enter the bloodstream and go to the brain, where it speeds up the central nervous system and adrenal receptors.
Within about 3-20 minutes after using the drug, your body will have a large release of hormones like serotonin, dopamine, norepinephrine, and adrenaline. Specifically, the adrenal effects from a big release of norepinephrine and adrenaline will trigger your body’s fight-or-flight response which is a big cause of the “meth eyes” appearance.
When your body and mind are in fight-or-flight mode, your pupils expand to let in more light. That’s why meth eyes will result in pupil dilation, light sensitivity, and reduced vision sharpness.
Other Short-Term Ocular Effects from Meth Use
Meth can also cause rapid eye movement from its heavy stimulatory effects. This can often lead to less blinking, which causes redness, dryness, and eye irritation. Some who smoke meth might also have their eyes get red and irritated from the smoke in the room.
It’s also common for someone struggling with meth abuse to experience sleep deprivation since the meth high can last for up to 12 hours. Therefore, their eyes may appear red with dark circles underneath from lack of sleep even when they aren’t high on the drug.
Lastly, meth can cause vasoconstriction, where the blood vessels in the eyes narrow and allow less blood flow through. In the short term, this could cause temporary vision loss when someone is high on meth.
Long-Term Ocular Effects
Prolonged methamphetamine use poses serious risks to eye health, some of which require immediate medical intervention. The following are notable ocular conditions associated with chronic meth use:
Keratitis
Keratitis, or corneal ulcer, is a potential result of long-term meth use. This condition involves inflammation of the cornea, the clear layer at the front of the eye. Several factors contribute to meth-induced keratitis, including:
- Vasoconstriction (reducing blood flow)
- Impaired pain sensitivity
- A diminished blinking reflex
- Irritation from smoke exposure
- Hand-to-eye contact introducing irritants
In some cases, individuals may develop neurotrophic keratitis, a condition characterized by reduced corneal sensation and delayed healing. If untreated, keratitis can result in permanent vision loss.
Endophthalmitis
Endophthalmitis is a serious infection of the internal eye fluids (aqueous and vitreous humor), often caused by bacteria or fungi entering through the bloodstream. This is most likely to happen when someone injects meth, and it can occur alongside meth-induced keratitis. Symptoms may include:
- Eye pain (though not always present)
- Vision reduction
- Eyelid swelling
- Redness
- Sensitivity to light
- Eye discharge or floaters
Endophthalmitis is a medical emergency that can progress to panophthalmitis, a more severe condition where the infection spreads throughout the eye and surrounding tissues. Without prompt treatment, complications may include vision loss, eye loss, or systemic issues like meningitis, sepsis, or even death.
Retinal Vasculitis
Retinal vasculitis refers to inflammation in the retina’s blood vessels. Though often painless, it can cause visual disturbances such as:
- Vision loss
- Floaters
- Blind spots (scotomas)
- Visual distortions (metamorphopsia)
- Altered color perception
In some cases, retinal vasculitis may present without noticeable symptoms.
Retinopathy
Meth use has been associated with various forms of retinopathy—abnormal changes in the retina. For instance:
- Ischemic retinopathy occurs due to restricted blood flow.
- Crystalline retinopathy involves the formation of small crystalline deposits on the retina.
Both conditions can lead to vision impairment and other complications.
Angle-Closure Glaucoma
Meth use, particularly with crystal or inhalable forms, has been linked to an increased risk of angle-closure glaucoma. This condition arises when the iris blocks the eye’s drainage angle, leading to a dangerous buildup of intraocular pressure. If untreated, it can severely damage the optic nerve and result in vision loss.
Keratolysis
Keratolysis, or corneal melting, involves the breakdown of the cornea’s thickest layer, the stroma. This condition can result in painful corneal ulcerations and significant vision loss. Both the preparation and smoking of methamphetamine have been identified as contributing factors.
Underlying Causes of Ocular Damage
As mentioned, one of the biggest underlying causes of long-term eye health issues from meth is vasoconstriction, which reduces blood flow to the eyes. You can experience vision loss from meth, severe irritation, altered color perception, and other serious effects due to this.
Meth is also known to cause long periods of wakefulness or trouble sleeping since it’s so stimulating. This can lead to a lot of redness and irritation in the eyes.
Red eyes from insomnia are also common when someone is experiencing meth withdrawal symptoms. However, studies have shown that sleep quality can improve with long-term abstinence from meth for four weeks or longer, so health markers can improve over time with the right treatment.
Treatment and Prevention
Ultimately, the best way to prevent meth eyes is to avoid using the drug. Since it can have so many negative effects on short and long-term health, it isn’t safe to use it.
If someone is struggling with meth addiction and the side effects it has on the mind and body, getting treatment as soon as possible is necessary to reduce the impact of its long-term health consequences. Visiting a drug treatment center is a great first step to getting a plan in place.
When eye problems have progressed, medical professionals may also recommend visiting an ophthalmologist (eye doctor) to diagnose issues and provide treatment options.
Conclusion
Meth abuse can have significant effects on the eyes and your overall health and well-being. Early intervention for meth addiction is important to prevent long-term health consequences and treat current symptoms.
If you or someone you care about is struggling with meth use, our team at United Recovery Project can help. We offer both medical detox and residential treatment options for drug and alcohol addiction at our facility. Our trained medical staff will create a comprehensive plan tailored to your needs.
Contact us today to learn more about getting started.
References
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- Manion, Garrett N., and Thomas J. Stokkermans. “The Effect of Pupil Size on Visual Resolution.” PubMed, StatPearls Publishing, 2024, https://www.ncbi.nlm.nih.gov/books/NBK603732/
- Seo, Jeong‐Woo, et al. “Methamphetamine Induces the Release of Endothelin.” Journal of Neuroscience Research, vol. 94, no. 2, 16 Nov. 2015, doi:10.1002/jnr.23697. https://pubmed.ncbi.nlm.nih.gov/26568405/
- Franco, Jimena, et al. “Methamphetamine-Induced Keratitis Case Series.” Cornea, vol. 41, no. 3, 26 May 2021, pp. 367–369, doi:10.1097/ico.0000000000002764. https://journals.lww.com/corneajrnl/abstract/2022/03000/methamphetamine_induced_keratitis_case_series.16.aspx
- Guo, Jingli, et al. “Bilateral Methamphetamine-Induced Ischemic Retinopathy.” American Journal of Ophthalmology Case Reports, vol. 15, 22 May 2019, pp. 100473–100473, doi:10.1016/j.ajoc.2019.100473. https://pmc.ncbi.nlm.nih.gov/articles/PMC6551529/
- Mahjoob, Monireh, and Samira Heydarian. “Changes in Corneal and Anterior Chamber Indices due to Methamphetamine Abuse.” Clinical and Experimental Optometry, vol. 105, no. 7, 30 Sept. 2021, pp. 721–725, doi:10.1080/08164622.2021.1983401. https://pubmed.ncbi.nlm.nih.gov/34592112/
- Heer, Jagdipak, et al. “Keratolysis Associated with Methamphetamine Use – Incidental Diagnosis of Corneal Melt in a Patient with Acute Methamphetamine Intoxication.” Clinical Practice and Cases in Emergency Medicine, vol. 4, no. 3, 15 June 2020, pp. 472–473, doi:10.5811/cpcem.2020.3.43981. https://pmc.ncbi.nlm.nih.gov/articles/PMC7434255/
- Ardani, Amir Rezaei, et al. “Does Abstinence Resolve Poor Sleep Quality in Former Methamphetamine Dependents?” Sleep Science, vol. 9, no. 3, July 2016, pp. 255–260, doi:10.1016/j.slsci.2016.11.004. https://www.sciencedirect.com/science/article/pii/S1984006316300888
