What Is the Relationship Between Alcohol and Obstructive Sleep Apnea?

Obstructive sleep apnea (OSA) is a respiratory disorder characterized by repeated collapses of the upper airway during sleep, leading to breathing pauses (apneas) or airflow reductions (hypopneas). These events cause decreased blood oxygen levels and frequent awakenings, resulting in fragmented sleep and daytime symptoms such as sleepiness and fatigue.¹

In recent decades, studies have explored how alcohol—a central nervous system depressant and muscle relaxant—may worsen the severity of OSA or increase its risk of occurrence. Classic risk factors for OSA include obesity, male sex, unfavorable airway anatomy, and older age. However, there is also evidence that lifestyle habits, particularly alcohol consumption, influence OSA.

Effects of Alcohol on the Severity of OSA

Several studies have shown that drinking alcohol before bedtime significantly worsens pre-existing OSA. Alcohol causes excessive relaxation of throat muscles during sleep, making it easier for the pharynx to collapse and trigger more obstructive events.² As a result, individuals with OSA experience an increase in the frequency and duration of apneas/hypopneas after consuming alcoholic beverages, as well as a more pronounced drop in oxygen saturation.

A systematic meta-analysis quantified this effect: on average, alcohol consumption increased the apnea-hypopnea index (AHI) by about 4 events per hour and reduced minimum oxygen saturation by approximately 2–3%, compared to a control night without alcohol.³ Moreover, the authors concluded that alcohol is associated with worsening OSA symptoms, including louder snoring, disrupted sleep architecture, and deeper oxygen desaturation. These findings indicate that even moderate amounts of alcohol can temporarily turn mild OSA into moderate or severe, increasing risks during sleep.

In the long term, regular alcohol consumption is also associated with a higher risk of developing OSA. Large observational studies that control for obesity and other factors have found that individuals who drink alcohol regularly have a higher prevalence of OSA compared to those who abstain.³

Proposed Pathophysiological Mechanisms

There are several mechanisms explaining why alcohol worsens airway obstruction during sleep:

1. Muscle Relaxation: Alcohol has a muscle-relaxing effect that reduces the tone of the pharyngeal dilator muscles—especially the soft palate and tongue—making the airway more likely to collapse under negative inspiratory pressure.² This excessive relaxation facilitates throat closure when the person is lying down and in deep sleep, contributing to the development or worsening of OSA.
2. Central Nervous System Depression: Alcohol acts as a depressant on the central nervous system,⁴ which affects the respiratory centers that regulate breathing and the tone of the pharyngeal muscles. As a result, the airway’s protective reflexes are reduced: the threshold for waking up due to suffocation is higher, and the ventilatory response to rising CO₂ or low O₂ is blunted. This central effect means that under the influence of alcohol, a person may take longer to wake up or increase respiratory effort during an apnea, making breathing pauses longer and oxygen drops more severe.
3. Sleep Architecture Disruption: Alcohol can also alter sleep architecture in ways that influence OSA. Initially, alcohol may induce drowsiness and facilitate sleep onset. However, it tends to increase awakenings throughout the night. This happens due to its acute effects: alcohol enhances GABAergic activity (which induces sleep) and modulates salience/reward circuits such as dopaminergic pathways, leading to fragmented sleep.⁵

It is also worth noting that the relationship between alcohol and OSA can be bidirectional in some aspects. Patients with untreated OSA often experience fatigue and insomnia, which in some cases may lead them to use alcohol as self-medication to fall asleep—a dangerous behavior. Recent population studies even suggest that individuals with OSA have a higher incidence of alcohol use disorder in the long term, although the mechanisms also involve complex psychosocial factors.⁶

Recommendations

The clinical implications of alcohol consumption in individuals with OSA are clear:
patients with OSA should avoid or minimize alcohol intake, especially in the hours leading up to bedtime. This recommendation is part of the broader lifestyle changes for managing OSA, alongside weight loss, physical activity, and sleep hygiene.

According to available evidence, abstaining from alcohol can reduce the severity of OSA. Some patients with mild OSA may notice fewer symptoms and respiratory events if they do not drink alcohol at night. It is also important for healthcare providers to assess alcohol habits in patients with suspected OSA: a history of significant alcohol consumption may increase diagnostic suspicion and point to the need for specific counseling.

References:

1. Platon, A. L., Stelea, C. G., Boișteanu, O., Patrascanu, E., Zetu, I. N., Roșu, S. N., Trifan, V., & Palade, D. O. (2023). An Update on Obstructive Sleep Apnea Syndrome-A Literature Review. Medicina (Kaunas, Lithuania), 59(8), 1459. https://doi.org/10.3390/medicina59081459 
2. Simon, L., Bourgeois, B. L., & Molina, P. E. (2023). Alcohol and Skeletal Muscle in Health and Disease. Alcohol research : current reviews, 43(1), 04. https://doi.org/10.35946/arcr.v43.1.04
3. Yang, S., Guo, X., Liu, W., Li, Y., & Liu, Y. (2022). Alcohol as an independent risk factor for obstructive sleep apnea. Irish journal of medical science, 191(3), 1325–1330. https://doi.org/10.1007/s11845-021-02671-7
4. Wolfe, M., Menon, A., Oto, M., Fullerton, N. E., & Leach, J. P. (2023). Alcohol and the central nervous system. Practical neurology, 23(4), 273–285. https://doi.org/10.1136/pn-2023-003817

5.Koob, G. F., & Colrain, I. M. (2020). Alcohol use disorder and sleep disturbances: a feed-forward allostatic framework. Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology, 45(1), 141–165. https://doi.org/10.1038/s41386-019-0446-0

6. Huang YP, Chien WC, Chung CH, Huang YC, Kuo SC, Chen CY, et al. Increased incidence of alcohol use disorder and alcohol-related psychiatric disorders in patients with obstructive sleep apnea: a nationwide population-based cohort study. Sleep Med. (2023) 101:197–204. doi: 10.1016/j.sleep.2022.10.031