Fucaceae
Bladderwrack
Fucus vesiculosus
⚠ Use with Caution
Caution in Pregnancy
Native to: North Atlantic and Pacific Oceans
Also known as: Common Bladderwrack, Rockweed, Black Tang, Sea Oak
Wikimedia Commons / CC BY-SA
Parts Used
Whole
Therapeutic Uses
Hypothyroidism (iodine deficiency), obesity (thyroid stimulation), chronic fatigue, rheumatic pain, digestive sluggishness. Traditional weight loss and thyroid herb.
Herbal Actions
Thyroid stimulant (iodine), anticoagulant (fucoidan), antiviral, prebiotic, anti-inflammatory, antioxidant
Active Constituents
Iodine (0.03–0.2%), fucoidan (sulfated polysaccharide), alginic acid, mannitol, phlorotannins, fucoidans, vitamins B and C, minerals
Preparation Methods
💊 Capsule🏺 Tincture☕ Herbal Tea
Traditional Preparation Notes
| Herbal Tea | 1 tsp dried seaweed per 250ml, steep 10 min, 1–2x daily |
| Tincture | 2–4 ml (1:5, 25% ethanol), 2x daily |
| Notes | Iodine content variable — standardized capsules preferred. Monitor thyroid function. Do not use as self-treatment for hypothyroidism without medical guidance — iodine excess can worsen thyroid conditions. |
Safety Information
Safety Rating
⚠ Use with Caution
Pregnancy
Caution in Pregnancy
Drug Interactions
⚠ Known interactions
Contraindications: Avoid in hyperthyroidism, Hashimoto's, with thyroid medications, anticoagulants. Heavy metal contamination risk — source carefully.
Side Effects: Iodine toxicity (thyroid disruption). Heavy metal accumulation with chronic use. GI upset. Hypersensitivity reactions.