For a 2-month-old infant, phenylephrine + chlorpheniramine combination drops are generally not routinely recommended for common cold. If prescribed, the dosing frequency should be used cautiously in this age group. Giving 0.5 ml every 6 hours (4 times/day) is relatively high for a young infant.
Next Steps
It would be advisable to reconfirm the exact dose and frequency with your treating pediatrician before continuing the medicine.
Health Tips
In most young infants, saline nasal drops and gentle suction before feeds provide good symptomatic relief.