Spirulina

Pronunciation: pronunciation varies by local usage.

Generic name
spirulina
Drug class
Blue-green algae (cyanobacterium) dietary supplement
Form
Not specified in reviewed sources
Route
Not established in reviewed sources
Legal status
Dietary supplement (not FDA‑approved as a drug)

Availability and supply rules vary by country

Trade names by country: United States

Australia: · Full directory

What spirulina is and how it works

Spirulina is a blue‑green algae (cyanobacterium, Arthrospira platensis) sold as a dietary supplement. It is not an FDA‑approved drug. (1)

Studied uses may include allergies, blood sugar management in diabetes, and high cholesterol or triglycerides. None of these are established treatments. Any use should be discussed with a healthcare provider, and spirulina must not replace prescribed medical therapy.

Mechanism of action: how spirulina works

Spirulina is a cyanobacterium (Arthrospira platensis). Detailed composition and pharmacodynamic characterization were not established in the reviewed sources. (1) (2)

What spirulina is used for

Allergies

Some studies suggest spirulina may help with allergies; evidence quality has not been formally graded in the reviewed source. (1)

Diabetes (blood sugar management)

Some studies suggest spirulina may help some people with diabetes manage blood sugar levels; no formal evidence-quality grading was provided in the reviewed source. (1)

High cholesterol and triglycerides

Some studies suggest spirulina may help some people lower cholesterol or triglyceride levels; no formal evidence-quality grading was provided in the reviewed source. (1)

Before taking spirulina

Do not take / not appropriate for

  • If you are pregnant or planning pregnancy, discuss with a healthcare provider before using spirulina; the reviewed source advises against use in this situation. (all products) (1)
  • If you are breastfeeding, discuss with a healthcare provider before using spirulina; the reviewed source advises against use in this situation. (all products) (1)

Tell your clinician about

  • If you have liver problems – spirulina should be used with caution.
  • If you have phenylketonuria (PKU) – spirulina should be used with caution.
  • If you have an autoimmune disease (examples: multiple sclerosis, lupus, rheumatoid arthritis, pemphigus vulgaris) – spirulina may stimulate immune activity and should be used with caution.
  • If you are at high risk of infection (e.g., transplant recipient, chemotherapy patient) – spirulina may stimulate immune activity and should be used with caution.
  • If you are taking any prescription or over‑the‑counter medicines or other supplements – spirulina may interact with a wide range of products (see Interactions). It may also interfere with certain laboratory tests.
(1)

How to take spirulina

  • No standardized dose has been established for spirulina in the reviewed sources; it is a dietary supplement without FDA‑approved dosing. Ask a healthcare professional or pharmacist for guidance on appropriate use for your situation.
  • Do not use spirulina as a substitute for prescribed medications.
(1)

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (2)

Missed dose

Missed-dose handling was not established in the reviewed sources. Ask a healthcare professional or pharmacist for product-specific guidance.

Overdose

No established toxic dose and no specific overdose-management guidance were found in the reviewed sources; if you suspect an overdose, contact your healthcare provider. Seek emergency care immediately for signs of a severe allergic reaction (see Serious Warnings). (1) (2)

Side effects

The primary documented side effect is upset stomach. A secondary, lower-confidence review of FDA MedWatch data (2001‑2009) reported nausea, diarrhea, vomiting, abdominal cramps, headache, dizziness, itching, and rash among non‑serious events. A separate lower-confidence secondary summary suggests no liver‑enzyme elevations or clinically apparent liver injury were linked to spirulina in controlled trials, though the underlying review was not directly verified in this pass.

Upset stomach / gastrointestinal symptoms

What to notice: Nausea, vomiting, diarrhea, abdominal cramps, stomach discomfort.

What to do: If symptoms are persistent or severe, consult your healthcare provider. They may suggest adjusting or discontinuing use. (1) (2)

Fatigue, headache, dizziness

What to notice: Unusual tiredness, headache, light‑headedness.

What to do: If these symptoms become bothersome, speak with your healthcare provider. (2)

Itching and rash

What to notice: Skin itching or rash after taking spirulina.

What to do: Seek medical advice promptly if an allergic reaction is suspected, and let the clinician advise whether spirulina should be continued. Seek emergency care immediately if signs of a severe reaction appear (see Serious Warnings). (2)

Severe allergic or adverse reaction

What to notice: Wheezing, chest tightness, fever, itching, severe cough, blue skin color (cyanosis), seizures, or swelling of the face, lips, tongue, or throat.

What to do: Seek emergency medical attention immediately. Do not delay because these can be life‑threatening. (1)

Serious warnings

Severe allergic or adverse reaction — emergency

Symptoms: Wheezing, chest tightness, fever, itching, severe cough, blue skin color (cyanosis), seizures, or swelling of the face, lips, tongue, or throat.

Action: Call emergency services or go to the nearest emergency room immediately. (1)

Interactions

Medicine or testEffectAction
Prescription and over‑the‑counter medicines and supplementsSpirulina may interact with products used for immune disorders, inflammation, high blood pressure, high cholesterol, viral infections, allergies, neurologic conditions, diabetes, weight loss, heart problems, osteoporosis, cancer, and blood clots. It may also interfere with laboratory tests.Give your healthcare provider a complete list of all medicines and supplements you take, and seek their advice before starting spirulina. (1)

Pregnancy, breastfeeding, kidney/liver function, age

Pregnancy

If you are pregnant or planning pregnancy, discuss with a healthcare provider before using spirulina; the reviewed source advises against use in this situation. (1)

Breastfeeding

If you are breastfeeding, discuss with a healthcare provider before using spirulina; the reviewed source advises against use in this situation. (1)

Liver disease

If you have liver problems, discuss suitability with a healthcare professional before using spirulina. (1)

Phenylketonuria (PKU)

If you have PKU, discuss suitability with a healthcare professional before using spirulina. (1)

Autoimmune disease

If you have an autoimmune disease (e.g., multiple sclerosis, lupus, rheumatoid arthritis, pemphigus vulgaris), discuss suitability with a healthcare professional before using spirulina, because it may stimulate immune activity. (1)

High infection risk

If you are at high risk of infection (e.g., transplant recipients, chemotherapy patients), discuss suitability with a healthcare professional before using spirulina, because it may stimulate immune activity. (1)

Children

No pediatric‑specific safety or dosing data were found in reviewed sources.

Monitoring

Before starting

  • Discuss potential benefits, risks, and interactions with a healthcare provider.
  • Review any pre‑existing conditions: liver disease, PKU, autoimmune disease, infection risk, pregnancy/breastfeeding status.
  • Inform your provider of all medications and supplements you are taking.

During treatment

  • Monitor for side effects, especially gastrointestinal symptoms, rash, itching, fatigue, headache, and signs of allergic reaction (see Serious Warnings).
  • Report any new or worsening symptoms to your healthcare provider.
  • Specific laboratory-monitoring requirements were not established in the reviewed sources.
(1) (2)

Storage

Storage instructions were not specified in the reviewed sources.

Professional information

Clinician‑facing context only. Spirulina is a dietary supplement without FDA‑approved therapeutic claims. This information is not a substitute for professional judgment or local product labeling.

All regions

Indication: Spirulina supplement use

Dose summary: No standardized dose has been established in the reviewed sources.

Renal context: No renal‑specific dosing data available. (1)

Mechanism of action

Hepatic guidance

No hepatic‑specific dosing established. Use with caution in liver impairment, per the reviewed source.

Overdose note

No established toxic dose and no overdose-management guidance were found in the reviewed sources. (1) (2)

Frequently asked questions

Is spirulina FDA‑approved?

No. Spirulina is sold as a dietary supplement and is not an FDA‑approved drug. (1)

Can spirulina help with allergies?

Some studies suggest it may help, though no formal evidence-quality grading was provided in the reviewed source. Speak with your healthcare provider before using spirulina for allergies. (1)

Is spirulina safe during pregnancy?

The reviewed source advises against using spirulina during pregnancy or when planning pregnancy. Discuss with a healthcare provider before use. (1)

What is the mechanism of action of spirulina?

Spirulina is a cyanobacterium (Arthrospira platensis). Detailed composition and pharmacodynamic characterization were not established in the reviewed sources. (1) (2)

What is the generic name of Spirulina?

The generic name is spirulina. (1) (2)

What class of drug is spirulina?

Spirulina is classed as: Blue-green algae (cyanobacterium) dietary supplement. (1) (2)

References

  1. Spirulina Uses, Benefits & Side EffectsDrugs.com (Natural Products Consumer Monograph) · United States · accessed 2026-08-05 · source 1
  2. Summary of Spirulina Adverse Events (January 2001-July 2009)FDA MedWatch (via secondary search summary) · United States · accessed 2026-08-05 · source 2
  3. SPIRULINA/CHLORELLA DROPS 2076 (SPIRULINA/CHLORELLA DROPS) LIQUID [PROFESSIONAL COMPLEMENTARY HEALTH FORMULAS] — US prescribing information (DailyMed SPL)U.S. National Library of Medicine (DailyMed) · US · accessed 2026-08-14 · source 3
  4. spirulina — RxNorm normalized drug concept (RXCUI 487252)U.S. National Library of Medicine (RxNorm) · US · accessed 2026-08-14 · source 4

Brand names by country

Single-ingredient spirulina names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries

United States

  • EarthriseEarthrise
  • Nutrex HawaiiNutrex Hawaii
  • Source NaturalsSource Naturals
  • HerbadietHerbadiet
  • NOWNOW
  • New SunNew Sun
  • Health Ranger SelectHealth Ranger Select
  • California Gold NutritionCalifornia Gold Nutrition
  • HealthForce SuperFoodsHealthForce SuperFoods
  • BioAnueBioAnue
View brands in additional countries.