Based on NIH | Is it safe to take naproxen on an empty stomach before exercising, or should I eat first to reduce the risk of stomach irritation or other side effects?

Taking naproxen on an empty stomach before exercise can be acceptable for some people, but it may increase the chance of stomach irritation, especially if you are prone to digestive issues. Nonprescription guidance commonly advises taking naproxen with a full glass of water and using food or milk if you experience stomach upset. ^{[1] [2]} Many people tolerate naproxen without food, but NSAIDs (like naproxen) can cause stomach lining irritation and, in rare cases, bleeding, particularly in higher‑risk individuals. ^{[3] [4]}

What official instructions say

• Nonprescription naproxen is usually taken with a full glass of water; using food or milk is suggested if stomach upset occurs. ^{[1] [2]}
• Over‑the‑counter naproxen labels warn about stomach bleeding signs (fainting, vomiting blood, black stools, persistent stomach pain) and advise stopping use and speaking to a clinician if they occur. ^{[5] [6]}
• NSAID medication guides note that ulcers and bleeding can happen at any time, sometimes without warning, and risk rises with certain factors (older age, alcohol, smoking, longer use, higher doses, corticosteroids, anticoagulants, SSRIs/SNRIs, prior ulcer or GI bleed). ^{[3] [7]}

Empty stomach vs. with food

• Food typically delays the peak level of naproxen (slower onset), but does not reduce the total amount absorbed. ^[8] This means taking it with food may make the pain relief kick in a bit later, but overall effectiveness is similar. ^[8]
• Experimental data suggest fasting can worsen gastric side effects of NSAIDs, while food may increase small bowel effects; however, this has not been definitively tested in humans. ^[8] Because naproxen can irritate the stomach lining, many users find that taking it with food or milk lessens nausea or dyspepsia. ^{[2] [5]}

Practical guidance before exercise

• If you rarely have stomach issues and need faster onset, taking naproxen with a full glass of water on an empty stomach may be reasonable for occasional use, provided you use the lowest effective dose and monitor for symptoms. ^{[1] [8]}
• If you have a sensitive stomach or any GI risk factors (history of ulcers, older age, alcohol use, smoking, concurrent blood thinners, steroids, SSRIs/SNRIs), it would be safer to take naproxen with a light snack or milk to reduce irritation. ^{[3] [7]}
• Regardless of food, always use the smallest effective dose and the shortest duration needed, and avoid combining with other NSAIDs. ^{[9] [4]}

Signs to stop and seek care

• Stop naproxen and seek medical advice if you feel faint, vomit blood, notice black or bloody stools, or have stomach pain that does not improve. ^{[5] [6]} Ulcers and bleeding can occur without warning in some cases. ^{[3] [4]}

Dosing and timing reminders

• Typical over‑the‑counter dosing: 220 mg every 8–12 hours as needed, not exceeding labeled limits; drink a full glass of water with each dose. ^[1]
• If you choose to eat, a small, non‑greasy snack (like yogurt, toast, or a banana) is often enough to buffer the stomach without excessively delaying onset. ^{[2] [8]}

Who should be extra cautious

• People with prior ulcers or GI bleeding, older adults, those on anticoagulants or corticosteroids, and those who smoke or drink alcohol have higher risk for NSAID‑related GI problems and may need alternatives or added protection. ^{[3] [7]}
• If you require frequent pre‑exercise pain control, consider discussing other strategies (topical NSAIDs, physical therapy, timing of doses, or GI protective measures such as proton pump inhibitors for high‑risk users) with a clinician. ^[10]

Bottom line

• It can be acceptable to take naproxen on an empty stomach for quicker relief if you do not have GI risk factors and you tolerate it well, but many people may benefit from a light snack to reduce stomach irritation. ^{[8] [2]} Always use the lowest effective dose for the shortest time, with a full glass of water, and watch for warning signs of stomach bleeding. ^{[1] [5] [3]}