Elderberry Supplements: What the Trials Show for Colds and Flu, and Who Should Skip Them

Elderberry is the dark purple fruit of the black elder tree (Sambucus nigra), promoted mostly for colds and flu (NCCIH). This guide covers elderberry itself, in adults.

The short version

• Colds and flu (syrup, lozenges or capsules, against placebo): small, mixed trials. Two small flu trials of one syrup and a cold trial found faster recovery, as did a 2019 pooling that added a lozenge trial, but the largest trial, in 87 people with lab-confirmed flu, found none. C Grade C (Wieland 2021; Macknin 2020).
• Raw or unripe berries, leaves and stems are poisonous: substances in them release cyanide and bring on nausea, vomiting and severe diarrhea; cooking removes them (NCCIH; LactMed 2025).
• Side effects in trials were few. Single case reports describe pancreatitis and autoimmune hepatitis (immune attack on the liver) in elderberry users, without proof of cause. D Grade D for these harms (Espinal 2026; Ramachandran 2022).
• Autoimmune disease: in lab tests elderberry raised inflammatory signals, and in one clinic's records 11 of 19 people with dermatomyositis or cutaneous lupus who took it had a flare afterwards. D Grade D (Barak 2001; Faden 2024).
• Pregnancy and breastfeeding: a 2014 review found no safety studies in pregnancy, and there are no data on breastfeeding (Holst 2014; LactMed 2025).

Does elderberry actually work for colds and flu?

C Grade C: a few small trials, mixed results. Our cold and flu season guide gives the same grade.

• Flu: in Norway, 60 adults ill for 2 days or less took elderberry or dummy syrup four times a day for 5 days, and felt better about 4 days earlier than the placebo group (Zakay-Rones 2004). In a kibbutz flu outbreak, 27 people aged 5 to 56 took the same syrup or placebo; 93% on elderberry improved within 2 days, most on placebo within 6 (Zakay-Rones 1995; Wieland 2021). Pooled, the two meant recovery about 2.7 days sooner, at very low certainty, with very different results (Wieland 2021).
• The largest flu trial: 87 people aged 5 and over (average age 25) with lab-confirmed flu in 3 US emergency rooms, some also taking the flu drug oseltamivir, took elderberry liquid or placebo for 5 days. Symptoms turned mild after 5.3 days on elderberry and 4.9 on placebo; full recovery took 8.6 and 8.7 days. A look-back analysis found elderberry alone, without oseltamivir, about 2 days worse than placebo alone (Macknin 2020).
• Colds: 312 air travellers took extract capsules or placebo from 10 days before a long-haul flight to 4 or 5 days after landing. Colds were not clearly fewer (12 against 17), but in the 29 who caught one, colds ran about 2 days shorter and milder (Tiralongo 2016; Wieland 2021). The extract's maker funded it and helped design it.
• Reviews: a 2021 systematic review found 5 trials: one of cold prevention, three of flu against placebo, and one comparing a hot drink of echinacea plus elderberry with oseltamivir. It concluded that elderberry may not cut your risk of a cold, and any shortening of colds or flu is uncertain. Of the 4 elderberry-only trials, 3 were company-sponsored and one included children. An earlier 2019 meta-analysis of the treatment trials, which also had data from a lozenge trial in 64 adults, found a benefit too; it rated the trials' risk of bias low on a checklist, while the 2021 team, using Cochrane tools, rated the certainty low to very low (Wieland 2021). A 2026 overview counted elderberry among herbs with some benefit, limited by flawed trials (Aghajafari 2026).

Our elderberry page also gives grade C. Elderberry or echinacea? The cold guide covers echinacea. In the hot-drink trial, 420 people with flu recovered about as often by day 5 on echinacea plus elderberry as on oseltamivir, but a blend against a drug can't show what elderberry does alone (Wieland 2021).

Does elderberry help your immune system, or COVID-19?

C Grade C: no change in immune markers in one 12-week trial. In 52 healthy women past menopause, capsules giving 500 mg a day of elderberry anthocyanins (purple pigments) for 12 weeks left CRP, IL-6 and TNF-alpha (blood markers of inflammation) no different from placebo. There is no set upper limit for elderberry; at that amount, liver and kidney tests stayed normal (Curtis 2009; Wieland 2021). For COVID-19, NCCIH says there is no good evidence, and the FDA and the Federal Trade Commission have acted against companies claiming it works (NCCIH).

Is elderberry safe if you have an autoimmune disease?

D Grade D: the concern rests on lab work and one records review. In the lab, immune cells from 12 healthy donors bathed in elderberry extract made far more inflammatory signals (cytokines), TNF-alpha 45 times more (Barak 2001). Trials in people have not shown this: the 12-week trial found no change in inflammation markers, and the 2021 review saw nothing to suggest elderberry overstimulates the immune system, though no study had looked at outcomes such as flares (Curtis 2009; Wieland 2021).

At one US clinic, of 673 adults with dermatomyositis or cutaneous lupus (autoimmune diseases of the skin and muscles), 19 had taken elderberry, and 11 of them (8 of 13 and 3 of 6) had a flare after starting it. The data came from chart notes and patients' reports; the authors call for studies that can test cause (Faden 2024). A case report also describes autoimmune hepatitis in a 60-year-old woman who had taken an elderberry supplement for several years (Ramachandran 2022).

With an autoimmune disease such as lupus or rheumatoid arthritis, or on hydroxychloroquine, transplant medicines or other immune-calming drugs, ask your specialist first. See systemic lupus erythematosus.

Are raw elderberries poisonous?

Raw or unripe ones can be. The raw or unripe fruit, leaves and stem hold cyanide-releasing substances that bring on nausea, vomiting and severe diarrhea, and large amounts can cause serious illness; cooking removes the toxin (NCCIH). The bark, leaves and root contain sambunigrin, which can release cyanide; cooked berries carry no such risk (LactMed 2025). In American elderberry, stems and green berries held the most, and commercial juice none measurable (Appenteng 2021). German poison centres found elder among only 8 common garden plants that caused at least moderate symptoms after accidental exposure, which in young children was mostly by swallowing fruit (Hermanns-Clausen 2019), and a 1984 CDC report covered elderberry juice poisoning in California (CDC 1984).

Elderflower or elderberry? Elderflower comes from the blossoms, which hold more of these compounds than the berries and differ in other chemistry (Senica 2017), and the main elder allergen is found in the pollen, flowers and berries (Förster-Waldl 2003). The cold and flu trials above tested berry products, not elderflower tea or cordial.

Syrup, gummies, capsules or tea: does the form matter?

Each trial used one product, so none shows the best form: syrup or liquid extract, 15 mL four times a day for 5 days from the start of flu symptoms (Zakay-Rones 2004; Macknin 2020); capsules of 300 mg of extract, 2 a day before travel and 3 a day while away, for about 2 weeks (Tiralongo 2016); lozenges with 175 mg of extract four times a day for 2 days (Wieland 2021); and juice, 177 mL to 355 g a day for a week (Rust 2023; Teets 2024). None tested gummies or tea. There is no set upper limit for elderberry, and at these amounts side effects were few: in the travel trial, 5 people reported problems (an itchy throat, tiredness, one case of kidney pain), 2 on elderberry and 3 on placebo, with the kidney pain on placebo, and the juice studies recorded no stomach upset (Tiralongo 2016; Rust 2023; Teets 2024). Products also vary: a 2024 review named elderberry among "immune health" botanicals found adulterated with cheaper ingredients, other plants or synthetic compounds (You 2024).

Does elderberry have vitamin C? Some: fresh berries of 13 varieties held 6 to 25 mg per 100 g (Kaack 1998). Adults need 75 to 90 mg a day, and above the adult upper limit of 2,000 mg a day, diarrhea, nausea and cramps become likely (NIH ODS).

Does elderberry help allergies, constipation, sleep or gut health?

• Allergies (hay fever): a 2020 review of 58 studies of supplements for hay fever listed those with promising evidence, and elderberry was not among them (Pellow 2020). Elderberry can itself cause allergy: 0.6% of 3,668 patients tested were sensitized to it (Förster-Waldl 2003).
• Constipation ("does elderberry make you poop?"): a tea of elder with anise, fennel and senna, a laxative, sped bowel transit in 20 people (15.7 against 42.3 hours on placebo) with a small drop in blood potassium while on it; with senna in it, it can't show what elder does alone (Picon 2010).
• Sleep ("does elderberry make you sleepy?"): in the travel trial, 2 people reported tiredness, one in each group (Tiralongo 2016).
• Gut health, grade D: in 18 adults with extra weight, a week of elderberry juice shifted gut bacteria against a placebo drink, and blood sugar after a test meal was 24% lower (Teets 2024); an earlier week-long trial, with 9 people analysed, found no difference in blood sugar (Rust 2023).

What we'd skip

• Homemade syrup, juice or tea from raw or unripe berries, leaves or stems (NCCIH).
• Elderberry in place of a flu vaccine or flu antivirals: the largest flu trial found no benefit, and elderberry alone did worse in a look-back analysis (Macknin 2020).
• Elderberry for COVID-19 (NCCIH).
• Daily elderberry to avoid colds: the prevention trial found no clear drop (Tiralongo 2016).

Safety and interactions

• Pancreas and liver (case reports): a 75-year-old woman on daily elderberry extract had mild pancreatitis that settled once she stopped; other causes were not ruled out (Espinal 2026). The autoimmune hepatitis case followed several years of use (Ramachandran 2022).
• Cancer medicines: a long-term elderberry user had severe nausea, loose stools and a fivefold rise in liver enzymes on pazopanib for sarcoma; all settled once every medicine stopped, and pazopanib restarted without trouble. Pazopanib is cleared by CYP3A4, a liver enzyme that handles many drugs; lab tests disagree on whether elderberry blocks it (Agarwal 2024). On cancer treatment, ask your oncology team first.
• Autoimmune disease or immune-calming medicines: ask your specialist first (Faden 2024).
• Other medicines: no studies have tested elderberry with apixaban (Eliquis) or other blood thinners, sertraline (Zoloft), escitalopram (Lexapro), levothyroxine, antibiotics, or blood pressure or diabetes medicines, and its effect on CYP3A4 has been studied only in the lab (Agarwal 2024). NCCIH advises asking your provider before combining it with any medicine (NCCIH). In 18 adults with extra weight but no chronic illness, a week of juice nudged thyroid hormone (T4) and TSH up slightly against placebo (Jarrett 2025); on levothyroxine, tell your prescriber.
• Upper limit: none is set for elderberry. The trial amounts (15 mL of syrup four times a day for 5 days; 600 to 900 mg of extract a day for about 2 weeks) were short-term with few side effects; the case reports involved daily or long-term use (Zakay-Rones 2004; Tiralongo 2016; Espinal 2026). Check my stack if you combine products.
• Pregnancy: a 2014 review found no human or animal safety studies in pregnancy and advised health workers not to recommend elderberry for colds or flu then (Holst 2014). Use it only as advised by your midwife or obstetric team.
• Breastfeeding? Ask your midwife, doctor or a lactation specialist, who can check what passes into breast milk. There are no data on elderberry in breast milk or its safety for nursing infants (LactMed 2025).
• Children: for babies, toddlers and children, ask your child's doctor before giving elderberry.

When to see a doctor

• Right away for trouble breathing or a high fever with flu; any breathing problem is an emergency (MedlinePlus).
• Within 2 days of flu symptoms if you are 65 or older, pregnant, or have asthma, diabetes, heart disease or another long-term condition: antiviral medicines work best started early (MedlinePlus).
• After eating raw elderberries, leaves or stems, with vomiting or diarrhea: call Poison Control (1-800-222-1222 in the US).
• Severe belly pain that spreads to the back, or yellowing of the skin or eyes, while taking elderberry: stop it and get checked the same day (Espinal 2026; Ramachandran 2022).
• A flare of an autoimmune disease after starting elderberry: stop it and tell your specialist.

Don't stop a prescribed medicine on your own; ask the prescriber or pharmacist. If pregnant, let your midwife or obstetric team guide you; anyone under 18 should ask a clinician first.

FAQ

Does elderberry actually work? Perhaps a little for flu and colds, but the trials are small and mixed (grade C), and the largest flu trial found no benefit. It does not replace a flu vaccine or antiviral medicine.

What are the side effects of elderberry? Commercial products caused few side effects in short trials. Eating the raw or unripe fruit, leaves or stems can bring on vomiting and severe diarrhea, and single case reports describe pancreatitis in a daily user and liver inflammation in a long-term user.

Can I take elderberry with Eliquis, Zoloft or Lexapro? No studies have tested elderberry with apixaban (Eliquis), sertraline (Zoloft) or escitalopram (Lexapro). Ask your prescriber or pharmacist before combining them.

Is elderberry safe for kids? Ask your child's doctor before giving elderberry to a baby, toddler or child.

Related pages

• Elderberry · Vitamin C
• Common cold · Common cold protocol · Flu · Upper respiratory tract infection · Immune health · Allergic rhinitis
• Guides: cold and flu season supplements · vitamin C · seasonal allergies · constipation
• Check my stack · How we grade

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