Clinical Research Directory

Inclusion Criteria: * aged 18-35 * individuals who menstruate, with painful periods * regular menstrual cycles (every 22-35 days) Exclusion Criteria: * presence of active pelvic or abdominal malignancies (primary or metastatic) * conditions associated with the absence of regular menses such as polycystic ovarian syndrome, pregnancy, or any current use of continuous hormonal medication or contraceptive * unable to read or comprehend the informed consent in English * presence of other diagnosed chronic back or pelvic pain conditions (including chronic back pain, fibromyalgia, bladder pain syndrome, irritable bowel syndrome, vulvar pain syndrome, and endometriosis-associated pelvic pain) * having another diagnosed/symptomatic chronic pain condition besides migraines with an average pain score \>3/10 in the last month when not consuming pain relievers, or that requires daily treatment with opioids (ex. hydrocodone, oxycodone, codeine, morphine, hydromorphone, tapentadol, tramadol) or neuromodulators (also known sometimes as antidepressants \[ex. amitriptyline, nortriptyline, imipramine, duloxetine, milnacipran, venlafaxine\] or antiseizure medications \[ex. topiramate, gabapentin, pregabalin, carbamazepine, lamotrigine\]) * current or past history of stomach ulcers * current or past history of gastrointestinal (GI) bleeding * diagnosis of peptic ulcer disease * current or past history of renal disorders * current or past history of adrenal dysfunction * diagnosis of liver disorders * diagnosis of chronic acid reflex (i.e. GERD) * Diagnosis of Crohn's disease or ulcerative colitis * Coagulopathy * Prolactinoma * Von Willebrand disease * Platelet disorders * High blood pressure that is difficult to manage * gastrointestinal conditions or surgeries that affect naproxen absorption * bleeding disorders * heart failure * a history of stroke * a history of heart attack * active genitourinary or sexually transmitted infection * allergy to non-steroidal anti-inflammatory drugs (NSAIDs) or their ingredients * individuals who take the following medications: anticoagulants (i.e. warfarin), lithium, diuretics, antacids, angiotensin-converting enzyme (ACE) inhibitors, methotrexate, cholestyramine, or probenecids. * Unmanaged diabetes (i.e. Fasting Blood Glucose: ≥ 126 mg/dL (≥ 7.0 mmol/L), Non-Fasting/Random Blood Glucose: ≥ 200 mg/dL (≥ 11.1 mmol/L), Hemoglobin A1c (HbA1c): ≥ 6.5%) * Uncontrolled thyroid function (i.e. Hypothyroidism (Underactive Thyroid): Thyroid-Stimulating Hormone (TSH): \> 4.5 mIU/L (mild) or \> 10 mIU/L (severe) Free T4: Below the lower end of the reference range (usually \< 0.9 ng/dL) * Hyperthyroidism (overactive thyroid) (i.e. TSH: \< 0.4 mIU/L (Suppressed or undetectable), Free T4: Above the upper end of the reference range (usually \> 2.0 ng/dL) * Liver dysfunction (i.e. Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) or bilirubin (unless known diagnosis of Gilbert's syndrome) ≥ 1.5 times the upper limit of the reference range) * Kidney dysfunction (i.e. Serum creatinine \> 1.1 mg/dL.)