Immune Wellness Safety: Recurrent Infections, Serious Symptoms and High-Dose Supplements

Urgent help first

Call your local emergency number (911 in the US) or go to emergency care right away if you or someone else has:

• sudden chest pain, severe difficulty breathing (gasping or not able to get words out), or is coughing up blood [1]
• difficulty breathing or inability to swallow, drooling, or a high-pitched sound when breathing [2]
• severe symptoms that are getting worse quickly [2]

Do not drive yourself; ask someone to drive you or call for an ambulance, and bring the medicines you take. [1] These signs come from NHS guidance and apply to adults and children; emergency numbers differ by country.

Poisoning (for example from raw elderberry parts or an overdose of a supplement): see poisoning: what to do first. In the US, Poison Help is 1-800-222-1222; for other countries see poison help by country.

Get medical advice soon (same day or within a few days)

The NHS advises urgent contact if flu symptoms occur and you are 65 or over, pregnant, have a long-term condition (such as diabetes or a heart, lung, liver, kidney, brain or nerve condition), have a weakened immune system, feel very unwell or short of breath, or symptoms do not improve after 7 days. [1] For colds, see a GP if you have a high temperature for more than 3 days, symptoms worsen, you feel short of breath or have chest pain, symptoms do not improve after 10 days, you have a cough for more than 3 weeks, or you have a long-term condition or weakened immune system. [3] Also seek urgent advice for signs of dehydration, such as passing less urine than usual or dark, strong-smelling urine. [2]

Repeated or unusual infections

A clinician may consider an immune problem when infections keep coming back or do not go away, when a severe infection comes from germs that do not usually cause severe infection, when treatment response is poor, or recovery is delayed or incomplete. [4] MedlinePlus says people with immunodeficiency get sick more often, and their infections may last longer and be more serious. [5] Several colds a year are normal and are not by themselves a sign of this: adults average 2 to 3. [6] See getting sick often and immunodeficiency and autoimmune conditions.

Transplant and immune-suppressing medicines

If you take immunosuppressants (for example after an organ transplant, or for autoimmune disease):

• Do not start any herb or supplement without asking your prescriber or pharmacist. NCCIH notes theoretical reasons to suspect echinacea may interact with immunosuppressants. [7]
• A review of tacrolimus found grapefruit, pomelo, ginger and turmeric can raise its levels and St. John's wort can lower them, reducing effect. [8]
• Reviewers advise that several herbal products can alter immune status or immunosuppressant blood levels, or harm kidneys or liver, and should be avoided in pediatric transplant recipients. [9]
• Never stop or change a prescribed medicine because of a product claim.

See how interactions work, interactions by drug class and St. John's wort interactions.

High-dose supplements

More is not safer. Upper-limit examples from the NHS (UK advice, pages last reviewed 2020): vitamin D, no more than 100 micrograms (4,000 IU) a day for adults; zinc supplements, no more than 25 mg a day unless advised by a doctor; vitamin C above 1,000 mg a day can cause stomach pain, diarrhea and gas. [10][11][12] Zinc excess reduces copper absorption and can cause anemia. [11] Garlic supplements may increase bleeding risk, which matters before surgery or with blood thinners. [13] Combination "immune" products can double up ingredients: see amounts and duplicate ingredients.

Products that claim to replace vaccines or treatment

Be wary of any product that promises to replace vaccines, antibiotics or prescribed medicines. No source we read supports that. Vaccines work by training the immune system to recognize specific germs. [14] The FDA and Federal Trade Commission have taken action against companies marketing elderberry products with unsubstantiated COVID-19 claims. [15] Immune health products are about 10% of US supplement sales, yet a review of 39 trials found gaps that prevent firm conclusions. [16] See evaluating safety claims, how supplements are regulated and vaccines and infection prevention.

Special groups

Little is known about elderberry in pregnancy and breastfeeding. [15] Echinacea has an allergy risk, and some children developed rashes; talk with a clinician before giving it to a child. [7] Do not give aspirin to children under 16 for cold or flu. [3] See pregnancy and breastfeeding and children and teens.