Clinical Scorecard: Alopecia Associated with Isoniazid in Cases of Isoniazid-Monoresistant Pulmonary Tuberculosis

At a Glance

Key Highlights

• Alopecia is a rare but significant adverse drug reaction during anti-tuberculosis treatment, often leading to treatment discontinuation.
• Isoniazid-induced alopecia typically presents as anagen effluvium with acute, reversible hair loss within 1–3 weeks of drug initiation.
• Discontinuation of isoniazid leads to hair regrowth within approximately one month and requires regimen adjustment, especially in cases of isoniazid monoresistance.

Guideline-Based Recommendations

Diagnosis

• Consider alopecia in patients on anti-tuberculosis treatment presenting with sudden hair loss.
• Use clinical examination and exclude other causes such as thyroid dysfunction and infections.
• Apply causality assessment tools like the Naranjo Adverse Drug Reaction Probability Scale.

Management

• Discontinue isoniazid if alopecia is suspected to be drug-induced, especially with moderate to severe hair loss.
• Substitute isoniazid with alternative agents such as moxifloxacin in cases of confirmed isoniazid monoresistance.
• Continue other anti-tuberculosis drugs as per national guidelines for drug-resistant TB.

Monitoring & Follow-up

• Monitor hair regrowth after discontinuation of the suspected drug.
• Observe for other adverse drug reactions during treatment modification.
• Regularly assess treatment adherence and psychological impact due to alopecia.

Risks

• Discontinuation of isoniazid without appropriate substitution may lead to treatment failure or development of further drug resistance.
• Psychological distress from alopecia may reduce patient adherence to anti-tuberculosis treatment.
• Rechallenge or desensitization carries risk of severe or life-threatening reactions and is generally not recommended.

Patient & Prescribing Data

Young adults receiving first-line anti-tuberculosis treatment including isoniazid

Isoniazid-induced alopecia is reversible upon drug discontinuation; regimen adjustment with moxifloxacin is effective in managing isoniazid monoresistant TB.

Clinical Best Practices

• Prompt recognition and diagnosis of alopecia as a potential adverse drug reaction during ATT.
• Use of causality assessment scales to support clinical decision-making.
• Timely discontinuation of the offending drug and substitution with effective alternatives.
• Close monitoring of patient psychological well-being and adherence during treatment changes.
• Reporting all adverse drug reactions to pharmacovigilance programs.

Related Resources & Content

• Naranjo Adverse Drug Reaction Probability Scale
• Tuberculosis Diagnosis and Treatment Guideline in Türkiye
• WHO Pharmacovigilance Program for TB Care (2012)