Thank you for sharing your concern in detail. Based on what you've described, the syrup itself is likely still safe if the cap was only externally exposed and no insects or contaminants entered the bottle.
However, to maintain hygiene and avoid any risk:
Do not drink directly from the cap going forward.
Always rinse the cap before and after use.
If the syrup inside looks, smells, or tastes abnormal, discard it.
Next Steps
Next Steps:
Continue using the syrup with a clean spoon or dosing cup. If in doubt, you can replace the bottle for safety.
Health Tips
Helpful Tip:
Store all medications in a cool, dry place and keep caps tightly closed to avoid attracting insects.
Word of Caution:
Avoid ingesting medicine contaminated by insects or improperly stored. While the chance of harm is low here, better hygiene ensures better health.