What is the maximum recommended dose of bilastine for patients aged 12 years and older, and does it require adjustment in renal or hepatic impairment?

Bilastine Maximum Dose and Dosing Adjustments

The maximum recommended dose of bilastine is 20 mg once daily for patients aged 12 years and older, with no dose adjustment required in renal or hepatic impairment. 1

Standard Dosing by Age

• Adults and adolescents ≥12 years: 20 mg once daily 1, 2
• Children aged 6 to <12 years: 10 mg once daily 1, 3
• Bilastine is not approved for children under 6 years of age 3

No Dose Adjustment Required in Special Populations

Renal Impairment

• No dosage adjustment is necessary regardless of the degree of renal insufficiency, including severe renal impairment (GFR ≤30 mL/min/1.73 m²) 1, 4
• Although bilastine exposure (AUC and Cmax) increases progressively with worsening renal function—ranging from 737.4 ng·h/mL in healthy subjects to 1708.5 ng·h/mL in severely impaired subjects—the elevated plasma concentrations remain well within established safety margins 4
• Renal excretion is the primary elimination route for bilastine, with approximately 95% excreted unchanged in urine and feces, and no alternative elimination pathways are activated even in severe renal insufficiency 4
• The 20 mg daily dose was well-tolerated across all degrees of renal impairment in clinical studies 4

Hepatic Impairment

• No dosage adjustment is required in patients with hepatic impairment 1
• Bilastine undergoes minimal hepatic metabolism and does not interact with the cytochrome P450 system, which eliminates concerns about drug accumulation in liver disease 1, 2

Elderly Patients

• No dosage adjustment is needed based on age alone 1
• The lack of significant metabolism and minimal drug-drug interaction potential makes bilastine particularly suitable for elderly patients who are often on multiple medications 1

Administration Considerations

Timing with Food

• Bilastine must be taken on an empty stomach—at least 1 hour before or no sooner than 2 hours after food intake 5, 2
• Food and fruit juice significantly slow bilastine absorption and reduce bioavailability, compromising efficacy 5
• This is a critical prescribing point that must be emphasized to patients to ensure therapeutic effectiveness 5

Safety Profile at Standard Dosing

• Bilastine demonstrates excellent tolerability even at above-standard doses 1
• It exhibits no anticholinergic effects, no cardiotoxic effects, minimal central nervous system penetration, and negligible sedative properties 1, 2
• No QT interval prolongation has been observed at therapeutic doses 2
• The most commonly reported adverse effect is headache, occurring at rates similar to placebo 2
• The safety profile in children aged 6-11 years receiving 10 mg daily is comparable to placebo 3

Common Prescribing Pitfalls to Avoid

• Do not reduce the 20 mg dose in elderly patients or those with renal/hepatic impairment unless specifically indicated by intolerable adverse effects; the standard dose is safe and effective across these populations 1, 4
• Do not allow patients to take bilastine with meals or immediately after eating; this is the most common error that reduces drug efficacy 5
• Do not prescribe doses exceeding 20 mg once daily in adults; this is the maximum approved dose and higher doses provide no additional benefit 1
• Do not assume bilastine requires the same food-independent dosing as other antihistamines; its unique pharmacokinetic profile mandates empty-stomach administration 5