Propylene Glycol (PG) allergies affect ~5% of vapers, often misdiagnosed as “vaper’s tongue.” Key signs:

• Symptoms: Throat swelling, hives, or gastrointestinal distress within 1 hour of vaping.
• Test It: Switch to max-VG liquids (e.g., 80% VG/20% water) for 48 hours.

PG-Free Alternatives:

1. Vegetable Glycerin (VG): Softer throat hit; best for sub-ohm devices.
2. MCT Oil: Rarely allergenic but avoid with coconut allergies.
3. TECS/TEA Salts: New synthetic bases (pH-balanced for smoothness).

Note: Always consult allergists before switching—PG-free liquids may require higher wattages.