Shilajit Side Effects: What the Evidence Shows

In the short human trials we could verify, shilajit was generally well tolerated, with no serious adverse events reported. But those trials were small, lasted 28 days to 48 weeks, and at least one excluded people with kidney disease, so they say little about long-term use or about people with existing conditions. The better-documented risk is the product itself: independent analyses have found metals above permissible limits in some samples. This page separates what has been observed from what is only theoretical.

Key Takeaways

• Researchers reported no serious adverse events in the trials we could verify. The one that itemized events (25 men, 28 days) listed mild ones such as acne, rash, and stomach discomfort, mostly rated unlikely related.
• Contamination is the best-documented risk. Some tested samples exceeded permissible metal limits, while other analyses found levels below thresholds, so product and batch matter.
• Case reports exist for an allergic reaction and for high blood pressure with low potassium in pregnancy. Each is one person.
• Many commonly repeated warnings (gout, thyroid, drug interactions, iron overload) are theoretical. We found no human data either confirming or ruling them out.
• Pregnancy, breastfeeding, kidney disease, and iron-overload conditions are the clearest “ask first” groups, mainly because there’s no safety data.
• The longest human trial we found ran 48 weeks. Nobody has published data on years of use.

What Human Trials Reported

Here is each human study that said something about safety, with the limits that go with it.

Healthy men, 28 days (2026). A single-arm Cureus pilot (Yadav et al.) gave 25 men 500 mg of resin daily. Seven participants (28%) reported mild events, all resolved without treatment: acne (2), and one each of rash, itching, upper abdominal pain, dyspepsia, cough, and fever. The rash, cough, and fever were rated “possibly related,” the rest “unlikely related.” Liver, kidney, and blood labs stayed within normal limits. There was no control group, so you can’t tell which events would have happened anyway, and most authors work for the product’s manufacturer.

Older adults on blood pressure drugs, 30 days (2023). In an open-label randomized trial (Patil et al., IJPP), 28 adults aged 60 to 80 added 500 mg of purified shilajit twice daily to their usual medication. The paper states that no adverse events occurred. It excluded people with kidney disease or diabetes.

Tibia fracture patients, 28 days (2020). A randomized, double-blind, placebo-controlled trial of 160 patients in Journal of Alternative and Complementary Medicine (Sadeghi et al.) gave two 500 mg capsules of momiai (a shilajit product) or placebo. The abstract reports no significant difference in adverse effects between groups. It’s the largest controlled safety signal we found, though adverse effects weren’t the primary outcome.

Postmenopausal women, 48 weeks (2022). The longest human trial we found randomized 60 women with osteopenia to placebo, 250 mg, or 500 mg of an aqueous shilajit extract (Pingali & Nutalapati, Phytomedicine). The abstract reports bone and inflammation outcomes but doesn’t describe adverse events, and we couldn’t access the full text to check.

Other trials. Studies in men for fertility (Biswas et al., 2010, 90 days, 28 completers) and testosterone (Pandit et al., 2016, 90 days, 250 mg twice daily versus placebo) are covered in our testosterone page. The fertility study’s abstract reports unaltered liver and kidney profiles. A 2016 study in overweight adults (Das et al.) called 8 weeks of 250 mg twice daily “well tolerated.”

What these add up to: no serious events reported in the trials we could check, mostly in healthy men over weeks to months. That’s not a safety profile for years of use, for people with other conditions, or for products other than the ones tested.

Contaminants: The Best-Documented Risk

Shilajit is a resin that forms in rock, so it carries whatever the rock contains. Three lines of evidence:

• Commercial and raw samples. A 2022 analysis in Biological Trace Element Research (Aldakheel et al.) tested shilajit of Indian and Pakistani origin and reported lead, arsenic, mercury, aluminum, and other metals “in amounts that exceeded the standard permissible limit.”
• Pooled literature. A 2024 review (Hussain & Saeed) cited limits of 10 ppm for lead and arsenic and 1 ppm for mercury in herbal drugs. Most reported levels were below those limits, “except in few studies where exceeded levels were reported.” The authors concluded that using shilajit without knowing permissible levels “is not safe.”
• A purified product in a trial. The chemical analysis of purified shilajit in the Patil trial paper listed lead at 0.017%, roughly 170 µg/g (170 ppm). That is above the 10 ppm limit cited in the review above, in a product described as purified, and the trial still reported no adverse events over 30 days. It is one product, and a short study can’t show long-term effects, but it is a reminder that “purified” on a label is not a lead test.
• Thallium. A 2025 BMC Chemistry study (Kamgar et al.) found thallium up to 0.5 µg/g in supplements, in some cases higher than in crude shilajit. They estimated up to 0.095 µg per pill and called for routine monitoring.

A 2026 analysis of twelve samples from different origins (Kamgar et al.) reported toxic metals below established thresholds. Levels clearly vary by source and batch, which is why a batch-specific certificate of analysis matters more than any claim of “purity.” Our guide to spotting fake or unpurified shilajit shows how to read one, and how shilajit is made covers what purification can and can’t remove.

For context, a 2008 JAMA study (Saper et al.) found that 20.7% of 193 Ayurvedic medicines bought online in 2005 contained detectable lead, mercury, or arsenic. That covers Ayurvedic products broadly, not shilajit specifically. A 2024 ConsumerLab test of eight shilajit products reported lead, cadmium, arsenic and mercury below its levels of concern at one dose a day, so results differ by product.

Documented vs. Theoretical Risks

This is the table to bookmark. “Documented” means someone observed it in people or measured it in products. “Theoretical” means it’s a reasonable worry with no direct shilajit evidence.

Risk	Status	Evidence
Mild stomach, skin, or cough events	Documented (mild)	7 of 25 men in a 28-day open-label pilot; most rated unlikely related. No control group.
Serious adverse events	Not reported	None in the trials above. Small and short, so absence isn’t proof.
Metal contamination	Documented in some products	Samples exceeding limits in one analysis; thallium detected; other analyses below thresholds.
Allergic reaction	Documented, single case	One woman with exercise-induced anaphylaxis, with shilajit as a possible cofactor (Losa et al., 2019). Skin tests were negative.
High blood pressure with low potassium	Documented, single case	A pregnant woman after six months of “mumijo,” treated with potassium and stopping the product (Stavropoulos et al., 2018).
Organ damage in people	Not shown	Liver and kidney labs stable in short trials.
Tissue changes in animals	Documented in rats at high doses	Negligible liver and intestine changes at 5,000 mg/kg for 91 days (Velmurugan et al.); mild to moderate liver and kidney changes in a single-dose acute toxicity study (Rizun et al., 2026). Doses far exceed supplement use.
Iron overload	Theoretical	Iron is present in shilajit; no human data on iron status.
Gout or high uric acid	Theoretical	Widely repeated; we couldn’t trace it to a clinical source.
Thyroid effects	Unknown	We found no human or animal thyroid study.
Blood sugar changes	Mostly unknown	No change in glucose in a small 2016 study of overweight adults; diabetes wasn’t a focus.
Drug interactions	Theoretical	No formal interaction studies found.
Pregnancy and breastfeeding harm	Unknown	No trial data; one case report above.

Iron and Hemochromatosis

A chemical analysis of purified shilajit described in the Patil trial paper listed iron at 0.77%, about 7.7 mg per gram. That’s one product, not a standard; a 2026 analysis of twelve samples (Kamgar et al.) found distinct variability in iron and other elements.

That matters for one group: people with hemochromatosis or other iron-overload conditions. The NIH’s hemochromatosis nutrition guidance says your doctor may recommend avoiding supplements that contain iron, and that some dietary and herbal supplements “may contain high levels of iron or unsafe chemical or herbal products.” No study has measured iron absorption from shilajit in people, and a rat study reported no significant change in iron levels except in the liver at the highest dose (direction not stated in the abstract), so this remains a precaution, not a documented harm. If you have iron overload, ask your doctor before starting, and ask the seller for an iron figure.

Kidneys, Uric Acid, and Gout

Kidney markers stayed stable in the few short trials that checked, but at least one of them screened out kidney disease. Metals and unlabeled minerals are the concern when kidneys can’t clear them well; see Is Shilajit Good for Kidneys?.

The gout warning is the one you’ll see most. We found no clinical study, case report, or published purine measurement behind it, and no human trial that reported serum uric acid. It’s unproven in both directions. If you have gout, kidney stones, or take uric-acid-lowering medication, ask your doctor and don’t change any prescription because of a supplement.

Blood Pressure, Blood Sugar, and Thyroid

Blood pressure. No human trial we found was designed to test whether shilajit raises or lowers it. Lead contamination, which a 2007 systematic review judged a causal contributor to hypertension, is the indirect route. Details are in Shilajit and Blood Pressure.

Blood sugar. The 2016 study in overweight and class I obese adults reported no change in blood glucose or lipids after 8 weeks. Diabetes wasn’t a stated focus, and the study wasn’t built to test glucose control. If you take insulin or glucose-lowering drugs, tell your clinician before starting and don’t adjust doses yourself.

Thyroid. We found no study of shilajit and thyroid function, so statements either way are speculation. If you take thyroid medication, mention the supplement to your clinician.

Drug Interactions: What Is Known

Nothing, formally. We found no interaction study between shilajit and any drug class. Everything below is theoretical reasoning from composition or from general supplement logic:

• Blood pressure drugs. The small 30-day Patil trial included people on several classes with no adverse events reported. Potassium content is a theoretical concern with ACE inhibitors, ARBs, and potassium-sparing diuretics.
• Diabetes drugs. Additive glucose lowering is hypothetical.
• Other drugs. No data. Minerals such as iron and calcium can affect absorption of some medicines, a general mineral issue, not a shilajit finding.

Bring the product and its lot number to a pharmacist, who can check it against your full list.

Pregnancy and Breastfeeding

There are no controlled studies in pregnant or breastfeeding women. The one published signal is the 2018 case report of high blood pressure and low potassium after six months of mumijo, which can’t show how common that is. Lead exposure is also a particular concern in pregnancy, and some products carry lead. “Insufficient data” is the honest label.

Side Effects for Women

Our shilajit for women page covers the claims. On safety:

• The only long trial in women we found (postmenopausal, 48 weeks) reported bone and inflammation outcomes; we couldn’t verify its adverse-event reporting.
• We found no study of shilajit and menstrual cycles, PCOS, or hormonal contraception, so any claim about those is untested.
• Both case reports we found (allergic reaction, pregnancy) involved women, but two cases can’t show a female-specific risk.
• Iron needs differ across life stages, so ask a clinician how the iron question applies to you.

Side Effects for Men

Most human shilajit research is in men, so the safety record is a little denser here. The 28-day pilot’s mild events included acne and a rash. The hormone angle is the unusual one. Studies reported higher total testosterone in two settings (Pandit et al.; Biswas et al.), and neither tested what that means over years. We found no study in men with hormone-sensitive conditions or on testosterone therapy; if either applies, ask your doctor. See benefits for men for what the studies claim.

Long-Term Use: What We Don’t Know

The longest human study we found lasted 48 weeks, and its abstract doesn’t report safety. The longest animal study we found ran 91 days. We can’t answer from the literature what cumulative metal exposure over years does, or how it affects people whose organ function changes slowly. If you take it long-term, use a batch certificate for metals, ask your doctor about periodic labs, and reassess why you’re taking it. Trial amounts are in our dosage guide.

Symptom vs. Likely Cause

This table is a way to think, not a diagnosis. “Possible” means plausible, not established.

What you notice	Possible causes	What to do
Stomach upset, nausea, loose stools	Mild event reported in a trial; taking on an empty stomach; sugar or additives in some formats	Take with food, pause, and see if it resolves. Talk to a clinician if it persists.
Rash, itching, hives	Allergy to shilajit or another ingredient	Stop. Seek care urgently for swelling, wheezing, or faintness.
Headache, dizziness, palpitations	Unclear; other ingredients (caffeine, herbs) in blends; blood pressure changes unrelated to shilajit	Stop, check your blood pressure, and ask your doctor, especially if you take medication.
High blood pressure with weakness or cramps	One case report of high blood pressure with low potassium	Stop and see a doctor promptly.
Persistent fatigue, abdominal pain, numbness, hair loss, nausea	Possible metal exposure from a contaminated product, among many other causes	Stop, keep the product and lot number, and ask a doctor about testing.

Who Should Avoid It or Ask First

• Pregnant or breastfeeding. No safety data.
• Anyone with kidney disease, dialysis, or a transplant. Excluded from trials; minerals and metals matter.
• Hemochromatosis or other iron overload.
• People on prescription medication, especially blood pressure, diabetes, or transplant drugs.
• People with a history of anaphylaxis or mast cell conditions. One case report involved this pattern.
• Anyone with gout, kidney stones, or thyroid disease, and children. The evidence is missing, so decide with your clinician.

When to Stop and See a Doctor

Stop immediately and get care for trouble breathing, swelling of the face or throat, fainting, or a severe rash. Stop and call your doctor for persistent vomiting, severe abdominal pain, new weakness or cramping, or a rapid or irregular heartbeat. Keep the container and lot number. For suspected poisoning in the US, call Poison Control at 1-800-222-1222.

For one format, see shilajit gummies side effects, where sugar and dose per piece add questions.

FAQ

Is shilajit safe?

In short trials in mostly healthy adults, no serious adverse events were reported. That’s not proven safe: the trials were small and brief, and contamination varies by product.

What are the most common shilajit side effects?

In the only trial we found that itemized them, mild items such as acne, rash, itching, stomach discomfort, cough, and fever each affected one or two of 25 men, and most were rated unlikely related. There was no control group.

Is shilajit safe to take every day for years?

We don’t know. The longest human trial we found was 48 weeks and the longest animal study 91 days. Metal exposure over time is the main open question.

Can I take shilajit with my medication?

No formal interaction studies exist. Tell your pharmacist or prescriber first, bring the product, and never change a prescribed dose based on a supplement.

Can shilajit cause heavy metal poisoning?

Some tested samples exceeded permissible limits, while other analyses found levels below thresholds. A batch-specific lab report with measured values is the practical safeguard.

Bottom Line

The evidence on shilajit side effects is thin but consistent so far: no serious events in a few short trials, a handful of mild ones, and two single-patient case reports. The risk with the best documentation is contamination, which varies by product and batch. Many popular warnings, including gout, thyroid, interactions, and iron overload, are theoretical, with no human data either way.

Choose a product with an independent metals report, skip it in pregnancy or kidney disease unless your clinician agrees, tell your doctor and pharmacist if you take medication, and stop if something feels wrong.