Pharmacokinetic Study of Topical Phenylephrine

A Phase 1 Open-Label Study to Evaluate the Pharmacokinetics of Topical Phenylephrine Applied to the Scalp in Healthy Adult Females

Inclusion Criteria:

• Healthy females, age 18-55
• BMI: 18-30 kg/m²
• Fitzpatrick Skin Types I-IV (to standardize absorption risk)
• Scalp free from irritation, dermatologic disease, or damage
• Able to refrain from using other topical scalp products

Exclusion Criteria:

• History of cardiovascular disease, hypertension, or arrhythmia
• Scalp infections, wounds, or significant hair loss
• Recent use of medications that interfere with CYP enzymes or adrenergic systems
• Known sensitivity to phenylephrine or ethanol
• Positive drug screen or abnormal ECG at screening

Female