Para-aminobenzoic acid (PABA) is a naturally occurring substance that is often used in sunscreen products. PABA is sometimes called vitamin Bx, but it is not a true vitamin.

This article discusses reactions due to PABA overdose and allergic response. PABA overdose occurs when someone accidentally or intentionally takes more than the normal or recommended amount of this substance.

This is for information only and not for use in the treatment or management of an actual poison exposure. If you have an exposure, you should call your local emergency number (such as 911) or the National Poison Control Center at 1-800-222-1222.

Para-aminobenzoic acid (also known as 4-aminobenzoic acid)

PABA is used in certain sunscreen and skin care products.

It may also naturally occur in the following products:

• Brewer's yeast
• Liver
• Molasses
• Mushrooms
• Spinach
• Whole grains

This list may not include all products that contain PABA.

• Coma
• Diarrhea
• Dizziness
• Eye irritation if it touches the eyes
• Fever
• Liver failure
• Nausea
• Rash (allergic)
• Shortness of breath
• Slowed breathing
• Stupor
• Vomiting

Note: Most PABA reactions are due to allergic reactions, not overdoses.