Dysmenorrhea in an 18-Year-Old: Diagnosis & Treatment

What This Likely Is

Step 1: Rule Out Secondary Dysmenorrhea

Treatment Protocol

First-Line: NSAIDs (Drug of Choice)

• Metoclopramide 10 mg orally or IM as antiemetic
• Ondansetron (if severe)
• Rectal/IM diclofenac as alternative route

Second-Line: Hormonal Contraceptives

• Combined oral contraceptive pills (OCP) - estrogen + progestin; inhibit ovulation, reduce endometrial proliferation, lower prostaglandin levels to early-proliferative phase levels
• Continuous/extended cycle OCPs are equally or more effective (fewer menstrual episodes = less pain)
• Levonorgestrel IUD (Mirena)
• Progestin-only pills, transdermal patch, vaginal ring, injectable progestin (DMPA) - all effective

Non-Pharmacological Options (Adjuncts)

• Heat therapy - local heat (heating pad) to the lower abdomen, similar efficacy to ibuprofen for mild-moderate pain
• Aerobic exercise - a 2025 meta-analysis (PMID 39887989) confirms aerobic exercise significantly reduces dysmenorrhea pain in adolescents and young women
• TENS (transcutaneous electrical nerve stimulation) - a 2024 systematic review (PMID 38366860) supports manual therapy and electrotherapy for dysmenorrhea relief
• Dietary changes - low-fat diet, omega-3 fatty acids, magnesium supplementation have some supporting evidence
• Acupuncture - meta-analysis showed benefit vs. NSAIDs and placebo

Third-Line (Refractory Cases)

• Add short course of weak opioid (codeine, hydrocodone) for 2-3 days per month
• Screen for psychological factors (anxiety, depression can amplify pain perception)
• Laparoscopy to definitively rule out endometriosis
• Rarely: surgical interventions (laparoscopic uterosacral nerve ablation, presacral neurectomy)

Practical Summary for This Patient

1. Start ibuprofen 400-600 mg every 6-8 hours beginning 1-2 days before the expected period, taken with food to reduce nausea
2. Add metoclopramide 10 mg at the onset of nausea/vomiting if needed
3. Apply heat to the lower abdomen
4. Reassess at 3-4 months - if insufficient relief, add a combined OCP
5. If still no response after 6 months of combined therapy, ultrasound + specialist referral for endometriosis workup

Important note: This is a clinical overview. The patient should be evaluated by a healthcare provider to confirm the diagnosis, rule out secondary causes, and tailor treatment to her individual history and contraindications.

Updated Assessment: Dysmenorrhea + Anemia

Two Causes of These New Symptoms

1. Iron Deficiency Anemia (Most Likely Primary Cause)

• Pallor (pale hands, pale conjunctiva, pale mucous membranes)
• Extreme weakness and fatigue
• Listlessness, poor exercise tolerance
• Lightheadedness
• The low blood pressure and near-fainting during periods

Iron deficiency develops insidiously: iron stores deplete first (falling ferritin), then serum iron falls, then hemoglobin synthesis drops, leading to microcytic hypochromic anemia, impaired work performance, and reduced immunocompetence. - Robbins & Kumar Basic Pathology, p. 394

2. Vasovagal / Prostaglandin-Mediated Hypotension

Investigations to Order NOW

• Mild: Hb 10-11.9 g/dL
• Moderate: Hb 8-9.9 g/dL
• Severe: Hb <8 g/dL (requires urgent management)

Comprehensive Treatment Plan

A. Treat Iron Deficiency Anemia

• Ferrous sulfate 325 mg (elemental iron ~65 mg) once to three times daily
• Take on an empty stomach for best absorption, or with vitamin C (ascorbic acid 200 mg) to enhance absorption
• If GI side effects (nausea, constipation) are intolerable, take with food or switch to ferrous gluconate or ferrous fumarate (gentler formulations)
• Continue for 3-6 months after Hb normalizes to replenish iron stores
• Creasy & Resnik's Maternal-Fetal Medicine, p. 1231

• Increase heme iron sources: red meat, chicken, fish
• Non-heme iron sources: spinach, lentils, beans, tofu, fortified cereals
• Pair with vitamin C-rich foods (citrus, tomato) to boost absorption
• Avoid tea, coffee, dairy within 1-2 hrs of iron tablets (these inhibit absorption)

• If Hb <7-8 g/dL, IV iron sucrose or ferric carboxymaltose may be needed
• Also indicated if patient cannot tolerate oral iron

B. Reduce Menstrual Blood Loss (Addresses Both Problems)

C. Manage Low BP & Weakness

• Increase fluid and salt intake - helps maintain circulating volume
• Avoid sudden standing - rise slowly to prevent orthostatic dizziness
• Iron correction will improve BP and weakness once Hb rises (usually takes 3-4 weeks for significant improvement)
• Encourage small, frequent meals to prevent post-meal BP drops

Red Flags - Refer Urgently If:

• Hb <7 g/dL (severe anemia - may need transfusion)
• Signs of hemodynamic instability (HR >100, systolic BP <90 mmHg at rest)
• Suspected secondary cause (fibroids, clotting disorder like von Willebrand disease)
• No response to iron therapy after 4 weeks (consider malabsorption, celiac disease, or wrong diagnosis)

Summary Action Plan

Week 1-2:
  ✔ CBC, ferritin, serum iron, TIBC, peripheral smear
  ✔ Start ferrous sulfate 325 mg daily with vitamin C
  ✔ Start ibuprofen 400-600 mg every 6-8 hrs from day 1 of period
  ✔ Add oral OCP (if no contraindication) to reduce bleeding + pain
  ✔ Dietary iron counselling

Month 1-3:
  ✔ Recheck Hb and ferritin at 4 weeks
  ✔ Continue iron for 3-6 months after Hb normalizes
  ✔ Pelvic ultrasound if bleeding remains heavy

Month 3-6:
  ✔ Reassess dysmenorrhea + anemia
  ✔ Consider LNG-IUD if heavy bleeding persists
  ✔ Specialist referral if secondary dysmenorrhea suspected

This patient's extreme weakness + pallor + low BP + heavy periods = iron deficiency anemia until proven otherwise. This is both treatable and reversible with consistent iron supplementation and reducing monthly blood loss. Please have her evaluated in person to check Hb urgently, especially if she is experiencing fainting or is unable to function.

Managing Vasovagal Syncope Triggered by Dysmenorrhea

What Is Happening Physiologically

PART 1: What To Do DURING an Episode (Acute Management)

Step 1 - If Prodrome Is Felt (Before Fainting)

• Sit or lie down instantly - do NOT try to stay standing
• Move to a cool, well-ventilated area
• Loosen tight clothing
• Take slow, deep breaths

Step 2 - If She Has Fainted (Loss of Consciousness)

1. Lay her flat on her back - do NOT prop her upright, do NOT put her in a chair
2. Elevate her legs 45° or higher (prop on a pillow, chair, or have someone hold them up) - this drains venous blood from the legs back to the heart immediately
3. Turn her head to the side if vomiting is present (she's already nauseous)
4. Do NOT give anything by mouth until fully conscious
5. Loosen tight clothing around the neck, chest, and waist
6. Keep her lying flat for at least 10-15 minutes after she regains consciousness - rising too quickly re-triggers the episode
7. Check for pulse - vasovagal syncope has a slow pulse (bradycardia); if no pulse, begin CPR and call emergency services

• Offer water + a light salty snack once fully awake
• Rise slowly: lying → sitting (wait 2 min) → standing (wait 2 min)

When to Call Emergency Services (999/112/911)

• Unconsciousness lasts >1-2 minutes
• She does NOT recover fully on her own
• Jerking movements / tongue biting (could be a seizure, not syncope)
• Chest pain or palpitations before fainting (possible cardiac cause)
• She is injured from the fall
• No pulse or abnormal breathing

PART 2: Preventing Future Episodes

A. Treat the Root Cause (Most Important)

B. Daily Lifestyle Measures (Non-Pharmacologic)

• Increase fluid intake to 2-3 liters per day (especially the week before and during periods)
• Increase salt intake (extra 2-4 g NaCl/day) to expand plasma volume - this is particularly effective in young women
• Compression stockings / tights during period days - reduces venous pooling in the legs
• Avoid triggers: prolonged standing, hot crowded environments, hot showers during periods
• Eat regular meals - hypoglycemia worsens susceptibility
• Sleep adequately - sleep deprivation lowers the vasovagal threshold
• Tilt training: Stand against a wall for progressively longer periods each day (20-40 mins) to desensitize baroreceptors - shown to reduce recurrence

C. Pharmacologic Prevention (If Lifestyle Fails)

Summary: Quick Reference Card

DURING PRODROME (nausea, dizziness, sweating):
  → Cross legs + tense muscles OR squat immediately
  → Sit/lie down at once
  → Cool environment, deep breaths

IF FAINTED:
  → Lay flat, legs elevated 45°
  → Head to side if vomiting
  → Stay flat 10-15 minutes after waking
  → Rise slowly in stages

PREVENT RECURRENCE:
  → NSAIDs 1-2 days before period
  → 2-3 L water/day + extra salt
  → Compression stockings on period days
  → Treat anemia (iron supplements)
  → OCP to reduce prostaglandin load

The single most effective long-term strategy for this patient is treating her dysmenorrhea aggressively - because the pain and prostaglandin surge are the primary trigger. Once the prostaglandin load is controlled with NSAIDs and/or hormonal therapy, vasovagal episodes should reduce significantly or stop altogether.