How should I evaluate and treat a 17‑year‑old female with several months of fatigue, mild orthostatic dizziness, heavy menstrual bleeding (five‑day flow with three days fully soaked pads) and no other abnormal findings?

Evaluation and Management of a 17-Year-Old with Fatigue, Orthostatic Dizziness, and Heavy Menstrual Bleeding

This patient's presentation is most consistent with iron deficiency anemia secondary to heavy menstrual bleeding (menorrhagia), and you should immediately obtain a complete blood count, ferritin, and beta-hCG, then initiate treatment with a levonorgestrel-releasing intrauterine device (LNG-IUD) as first-line therapy for the heavy bleeding. 1, 2, 3

Immediate Diagnostic Workup

Rule out pregnancy first with a beta-hCG test in all reproductive-age women presenting with abnormal bleeding or fatigue, even if the patient reports not being sexually active. 1, 2, 3

Obtain these specific laboratory tests:

• Complete blood count with differential to assess for anemia (hemoglobin, hematocrit, MCV) 2
• Serum ferritin to evaluate iron stores 2
• Thyroid-stimulating hormone (TSH) to exclude hypothyroidism as a cause of fatigue and menstrual irregularity 4
• Consider coagulation studies (PT, aPTT, von Willebrand factor) if bleeding is severe, as up to 20% of women with heavy menstrual bleeding have an underlying bleeding disorder 1, 2

Assess orthostatic vital signs properly: Measure blood pressure and heart rate both supine and standing. A drop of 20 mmHg systolic and/or 10 mmHg diastolic within 3 minutes of standing confirms orthostatic hypotension and suggests the dizziness is related to blood volume depletion from chronic blood loss. 4

Defining Heavy Menstrual Bleeding in This Case

This patient clearly meets criteria for menorrhagia: she reports 3 days of fully soaked maternity pads, which far exceeds normal menstrual blood loss. Bleeding that saturates a large pad hourly for at least 4 hours requires urgent evaluation. 3

First-Line Treatment for Heavy Menstrual Bleeding

The levonorgestrel-releasing intrauterine device (LNG-IUD) is the single most effective medical treatment available, reducing menstrual blood loss by 71-95%. 1, 2, 3 This addresses both the underlying heavy bleeding and provides superior contraceptive efficacy. 1 Over time, many women experience only light menstrual bleeding or amenorrhea with the LNG-IUD. 2

Alternative first-line options if LNG-IUD is declined or contraindicated:

• NSAIDs (mefenamic acid or naproxen) for 5-7 days during menstruation only can reduce menstrual blood loss through prostaglandin inhibition 1, 2, 3
• Critical contraindication: Avoid NSAIDs in women with cardiovascular disease, history of myocardial infarction, or thrombosis risk 1, 2, 3
• Combined oral contraceptives can stabilize the endometrium through estrogen's proliferative effects, but carry higher thrombotic risk than progestin-only methods 1

Iron Replacement

Once anemia is confirmed, initiate oral iron supplementation (ferrous sulfate 325 mg daily or three times daily depending on severity). 2 The fatigue and orthostatic dizziness will improve as hemoglobin normalizes, typically over 4-8 weeks.

Counseling and Follow-Up

Enhanced counseling about expected bleeding patterns significantly improves treatment adherence and reduces discontinuation. 1, 2 Reassure the patient that irregular bleeding with hormonal treatments is generally not harmful and does not indicate contraceptive failure. 1

Schedule follow-up in 2-4 weeks to:

• Review laboratory results
• Assess response to iron supplementation
• Evaluate tolerance of menstrual bleeding treatment
• Recheck hemoglobin if initially anemic

When to Refer to Gynecology

Consider gynecology referral if heavy bleeding persists despite 6 weeks of appropriate medical management. 1 However, given this patient's age and classic presentation, initial management in primary care is appropriate.

Common Pitfall to Avoid

Do not dismiss the orthostatic dizziness as a primary vestibular or neurologic problem when the patient has clear evidence of heavy menstrual bleeding. 5 The timing and triggers are key: dizziness on standing in the context of chronic blood loss points directly to volume depletion and anemia, not a peripheral vestibular disorder. 5

Addressing the Insect Bites

The fading erythematous areas with no signs of infection require no specific treatment beyond reassurance. These are incidental findings unrelated to the primary complaint of fatigue.