What the trials found
The published human trials reported shilajit as generally well tolerated, with no serious adverse effects described.[1][2] A safety review reached a similar conclusion.[4] Those trials were small and short, though, so uncommon side effects might not have appeared; see adverse events and case reports.
Side effects people commonly describe
| Effect | What to try |
|---|---|
| Stomach upset or nausea | Take with food; reduce to the lower end of the label serving |
| Headache | Stop and see whether it resolves |
| Dizziness or light-headedness | Stop; seek advice if it persists or you take blood pressure medicines |
| Feeling flushed or warm | Stop if uncomfortable |
| Poor sleep | Take earlier in the day; see sleep |
These reports are anecdotal and can’t be attributed to shilajit with certainty, but they are worth taking seriously.
Allergic reactions
Mild allergic reactions include a rash, itching or hives. Stop taking shilajit and speak to a pharmacist or GP. Call 999 immediately for signs of a severe reaction (anaphylaxis): swelling of the lips, tongue or throat, difficulty breathing or swallowing, wheezing, feeling faint, or collapse.
Allergic reactions to shilajit are rarely reported, but any supplement can cause them. People who react to one product may also be reacting to an added ingredient, such as a capsule shell or gummy flavouring.
Effects linked to contamination
Some risks come from what is in a particular product rather than shilajit itself. Metals such as lead can accumulate over time without obvious symptoms at first, and microbial contamination can cause stomach upset. Research has found metals in some Ayurvedic products bought online and thallium in some shilajit supplements.[5][3] That is why a batch-tested product is the most important way to reduce side-effect risk; see heavy metals.
Who is more likely to have problems
People taking several medicines, older adults, people with kidney, liver or other long-term conditions, and anyone taking more than the label serving have more reason for caution. Shilajit isn’t recommended for children or in pregnancy; see existing conditions, older adults and pregnancy.
Reducing your risk of side effects
- Batch-tested productWith metals and microbiology results.
- Start within the label servingMeasured consistently.
- Introduce it on its ownSo any effect is easier to identify.
- Take with food if neededTo reduce stomach upset.
- Check medicines firstWith a pharmacist.
If you have a side effect
Stop taking it, keep the jar and batch number, and seek advice from a pharmacist, GP or NHS 111. You can report suspected reactions through the MHRA Yellow Card scheme, and food safety concerns to the Food Standards Agency.[6] Tell the seller too, so they can check the batch; see how to report a problem.
Should you try again?
After an allergic reaction, don’t take that product again. After a mild effect such as stomach upset, some people try again later with food or a smaller serving within the label amount, but if the effect returns, stop for good.
Keep a short symptom note
When you start shilajit, a brief note of the date, the product, the batch number and your serving makes it much easier to connect any new symptom to the supplement, or rule it out. Share it with your pharmacist or GP if you seek advice.
Reactions to other ingredients
If you react to a capsule, gummy or blend, the cause may be another ingredient, such as gelatine, colourings, sweeteners or herbs. Check the full ingredients list and mention it when seeking advice; see reading a label.
Putting it into practice
Start with a batch-tested product at the label serving, taken with food if your stomach is sensitive, and note any changes in the first few weeks. Stop for anything unusual and seek advice.
Telling your doctor
Many people don’t mention supplements to their doctor. Doing so helps your doctor recognise possible side effects and spot patterns across patients.
The bottom line
Shilajit is generally well tolerated in small trials, and the side effects people describe are usually mild. Allergic reactions are rare but need prompt action. Choose a batch-tested product, introduce it on its own, and stop and seek advice if anything unusual happens.
Frequently asked questions
What are the side effects of shilajit?
People most often describe mild effects such as stomach upset, nausea, headache, dizziness or feeling flushed.
Can shilajit cause an allergic reaction?
Rarely. Stop for a rash or itching; call 999 for swelling of the face or throat or difficulty breathing.
Did the clinical trials report side effects?
Why does shilajit upset my stomach?
Some people find it irritating on an empty stomach. Try taking it with food.
Can shilajit cause headaches?
Some people report headaches. Stop and see whether they resolve.
Can side effects come from contamination?
Yes. Metals and microbes in a poor product can cause problems, which is why batch testing matters.[3]
How do I report a side effect?
Via the MHRA Yellow Card scheme or to the Food Standards Agency, after seeking medical advice.[6]
Should I stop shilajit if I feel unwell?
Yes. Stop and seek advice; see when to stop.
Sources & further reading
Primary research, regulators and standards bodies are cited first. A source being listed here does not mean it supports every claim made by sellers; it supports the specific statement it is attached to.
- Pandit S, Biswas S, Jana U, De RK, Mukhopadhyay SC, Biswas TK. Clinical evaluation of purified Shilajit on testosterone levels in healthy volunteers. Andrologia 48(5):570–575, 2016. PMID 26395129. View source (opens in a new tab) [Randomised controlled trial]
- Pingali U, Nutalapati C. Shilajit extract reduces oxidative stress, inflammation, and bone loss to dose-dependently preserve bone mineral density in postmenopausal women with osteopenia: a randomized, double-blind, placebo-controlled trial. Phytomedicine 105:154334, 2022. doi:10.1016/j.phymed.2022.154334; PMID 35933897. View source (opens in a new tab) [Randomised controlled trial]
- Quantifying of thallium in Shilajit and its supplements to unveil the potential risk of consumption of this popular traditional medicine. BMC Chemistry 19:20, 2025. doi:10.1186/s13065-025-01384-7. View source (opens in a new tab) [Laboratory analysis]
- Stohs SJ. Safety and efficacy of shilajit (mumie, moomiyo). Phytotherapy Research 28(4):475–479, 2014. PMID 23733436. View source (opens in a new tab) [Review]
- Saper RB, Phillips RS, Sehgal A, et al.. Lead, mercury, and arsenic in US- and Indian-manufactured Ayurvedic medicines sold via the Internet. JAMA 300(8):915–923, 2008. View source (opens in a new tab) [Cross-sectional product survey]
- Food Standards Agency. How to report a food safety or hygiene issue for members of the public. GOV.UK, 2026. View source (opens in a new tab) [Regulator guidance]