PABA: Uses, Benefits, Dosage & Safety
Last updated: June 2026 · Reviewed by the FactoWiki Editorial Team for clarity and source accuracy
Quick summary
PABA (para-aminobenstoic acid) is a compound once classed with the B-vitamins and used in old sunscreens and for some skin conditions. Modern evidence for oral use is limited and high doses can be risky.
What is PABA?
Para-aminobenzoic acid (PABA) is an organic compound that was historically grouped with B-vitamins. It was widely used in early sunscreens (applied to skin) and is sometimes taken orally in alternative medicine.
What PABA is commonly used for
In supplements, PABA is most often included for skin & anti-aging support. It is used as nutritional support, not as a treatment for any medical condition — the distinction matters, because the claims on a sales page are often stronger than the evidence allows.
How PABA works
PABA is part of the folate molecule in bacteria and absorbs UV light, which is why it was used in sunscreens. Its proposed oral effects on skin and pigmentation are not well explained mechanistically.
What the evidence says
Here's an honest snapshot of what published research suggests about PABA — including where the evidence is limited.
- Topical PABA blocks UV but was largely abandoned because it stains clothing and causes allergic reactions. Oral PABA has been studied for conditions like Peyronie's disease and scleroderma with weak, inconsistent evidence.
- Study quality and doses vary, and a result seen in research doesn't guarantee the same for any individual — use the sources below to check the current evidence on PABA rather than relying on marketing claims.
Typical dosage used in studies
There is no established dietary requirement. Therapeutic oral doses used in older studies were high (several grams per day) and are not recommended without medical supervision. This is general information from research, not a personal recommendation or a dosing instruction.
Side effects and safety
High-dose oral PABA can cause nausea, skin rash and, rarely, liver problems, and it can interfere with certain antibiotics. It is not an essential nutrient and routine supplementation is not advised. As with any supplement, it's sensible to introduce PABA on its own, use a trusted brand, and stop if you notice any reaction.
Medication interactions and who should avoid PABA
Medication & safety check
Vitamins are safe at normal doses, but high-dose supplements can interact with medication and with other nutrients — affecting absorption or blood levels. If you take any regular medication, are pregnant or breastfeeding, or manage a health condition, confirm PABA is appropriate for you before starting.
This is general information, not personal medical advice. If you take any medication, are pregnant or breastfeeding, or have a health condition, confirm it's safe to use PABA with your doctor or pharmacist first.
Sources & further reading
For authoritative background and the current research base on PABA, consult:
- PubMed — search the research on PABA
- NIH Office of Dietary Supplements — fact sheets
- MedlinePlus (U.S. National Library of Medicine)
- MedlinePlus — drugs, herbs & supplements
Frequently asked questions
Does PABA actually work?
Topical PABA blocks UV but was largely abandoned because it stains clothing and causes allergic reactions. Oral PABA has been studied for conditions like Peyronie's disease and scleroderma with weak, inconsistent evidence. As with most supplements, results vary between people and the marketing is often stronger than the evidence — so it's worth checking the research before relying on it.
Is PABA safe to take?
For most healthy adults at normal doses it's generally well tolerated, but there are real cautions. High-dose oral PABA can cause nausea, skin rash and, rarely, liver problems, and it can interfere with certain antibiotics. It is not an essential nutrient and routine supplementation is not advised. If you take medication, are pregnant or breastfeeding, or have a health condition, check with a doctor or pharmacist first.
What is PABA used for?
In supplements, PABA is mainly included for skin & anti-aging support — as nutritional support, not as a treatment for any medical condition.
Where you'll find PABA
On FactoWiki, PABA is the kind of ingredient you'll see discussed in these supplement categories. Each category guide breaks down what the evidence does and doesn't support.
Related ingredients to explore
Ingredients often studied or formulated alongside PABA — useful for understanding the full picture of a formula.