I have pruritus after starting Tessalon (benzonatate); how should I manage it?

Management of Benzonatate (Tessalon Perles)-Induced Pruritus

Discontinue benzonatate immediately, as pruritus represents a drug-induced adverse reaction that requires cessation of the causative medication. 1, 2

Immediate Action

• Stop benzonatate (Tessalon Perles) immediately upon recognition of pruritus, as this is the fundamental principle of managing drug-induced itch 1, 2
• Drug-induced pruritus is defined as generalized itching without skin lesions caused by a medication, and the primary treatment is discontinuation of the suspected causative drug 2
• Assess whether there are any skin lesions present; if absent, this confirms drug-induced pruritus rather than a drug-induced rash 2
• Evaluate the severity and timing: note when pruritus started relative to benzonatate initiation and whether it is localized or generalized 1

Symptomatic Management While Pruritus Resolves

For Mild Localized Pruritus (Grade 1)

• Apply moderate-potency topical corticosteroids such as mometasone furoate 0.1% or betamethasone valerate 0.1% ointment to affected areas 1
• Use emollients regularly to maintain skin hydration and prevent xerosis, which can worsen itching 1, 3
• Consider topical menthol 0.5% for additional symptomatic relief through counter-irritant effects 1
• Monitor for 2 weeks; if symptoms worsen or persist, escalate treatment 1

For Moderate to Severe Pruritus (Grade 2)

• Non-sedating antihistamines for daytime use: loratadine 10 mg once daily or fexofenadine 180 mg once daily 1, 3
• Sedating antihistamines for nighttime use: hydroxyzine 25-50 mg at bedtime or diphenhydramine 25-50 mg at bedtime to break the itch-scratch cycle 1, 4
• Continue topical corticosteroids and emollients as above 1
• Reassess after 2 weeks; if no improvement, proceed to next step 1

For Refractory or Severe Pruritus (Grade 3)

• GABA agonists as second-line systemic therapy: gabapentin 900-3600 mg daily or pregabalin 25-150 mg daily 1, 3
• Start gabapentin at lower doses and titrate upward based on response and tolerability 3
• Tricyclic antidepressant doxepin 10 mg twice daily may be considered as an alternative, particularly if antihistamines fail 3, 4
• Consider dermatology referral if symptoms remain refractory to these interventions 4

Critical Pitfalls to Avoid

• Do not continue benzonatate even if pruritus is mild, as drug-induced reactions can progress unpredictably 1, 2
• Do not use topical corticosteroids for more than 2 weeks continuously without reassessment, as prolonged use can cause skin atrophy 1
• Avoid long-term sedating antihistamines (beyond what is needed for symptom resolution) except in palliative care settings, as chronic use may increase dementia risk in elderly patients 3
• Monitor for signs of DRESS syndrome (Drug Rash with Eosinophilia and Systemic Symptoms): fever, facial edema, lymphadenopathy, or systemic symptoms, which would require immediate medical evaluation and possible systemic corticosteroids 5

Expected Timeline

• Pruritus typically resolves within days to weeks after discontinuation of the causative medication 2
• If itching persists beyond 2-4 weeks after stopping benzonatate, investigate alternative causes of pruritus and consider specialist referral 1, 3
• Vigorous symptomatic antipruritic treatment should be undertaken if the causative drug cannot be stopped or if itching persists after drug withdrawal 2

Alternative Cough Management

• Discuss alternative antitussive options with the prescribing physician, as benzonatate should not be restarted given the adverse reaction 2
• Consider non-pharmacologic measures or alternative cough suppressants that do not share cross-reactivity 2