Who should not take slippery elm?

No clinical trial has tested slippery elm in a way that defines who should avoid it — the caution here comes from documented historical harm and general safety reasoning, not from a study that excluded specific groups and explained why.

There's no evidence it damages the kidneys

No published study found for this page connects oral slippery elm to kidney damage. That doesn't mean the possibility has been specifically ruled out by research — it means no study has looked, in either direction. If you have kidney disease, ask a doctor before adding any new supplement, slippery elm included, since reduced kidney function changes how the body handles many things, not because of a specific documented risk here.

Who should ask a doctor first

• Pregnancy or breastfeeding: ask a doctor before using any form of slippery elm, given the historical association above and the general lack of safety research in pregnancy for any oral form.
• Children: ask a doctor before giving slippery elm to a child — none of the human studies referenced across this site involved children, so there's no dosing or safety information specific to them.
• Kidney disease or liver disease: ask a doctor first, since there's no documented problem connecting slippery elm to either, but no safety study has specifically included people with kidney disease or liver disease either.
• Anyone on prescription medication: see slippery elm and medications: what to check before combining them, especially for a medication with a narrow safe range.

Questions people ask

Can slippery elm cause kidney damage?

No study found for this page reports slippery elm, taken by mouth, causing kidney damage. If you have kidney disease, ask a doctor before adding any supplement regardless, since impaired kidney function changes how the body processes many things.

Can slippery elm cause liver damage?

See slippery elm side effects — a liver-safety reference found no evidence connecting slippery elm to liver injury or raised liver enzymes.

Is slippery elm safe during pregnancy?

Ask a doctor before using any form of slippery elm during pregnancy. There's no dedicated safety research on oral slippery elm during pregnancy either way.

Who should not drink slippery elm tea?

Anyone pregnant or breastfeeding, giving it to a child, living with kidney disease or liver disease, or taking prescription medication should ask a doctor first, for the reasons described above rather than because tea specifically was tested and excluded.

Related reading: slippery elm dosage and slippery elm benefits: what the research does and doesn't show.