Chemical Warfare Peak O2 is an adaptogenic mushroom blend that helps boost oxygen uptake to support endurance and help you push harder in training. Six organic certified mushrooms: Cordyceps, Reishi, Lion's Mane, Chaga, Turkey Tail and Maitake, work together to support oxygen use and stamina. From a brand rooted in quality and transparency, Peak O2 is produced under GMP standards and USDA Organic certification.

Available Sizes & Variants:

120g Peak O2 - mushroom supplement for endurance.

Benefits & Features:

• Boosts endurance by improving oxygen uptake during exercise.
• Supports faster recovery through reduced lactate buildup.
• Organic mushroom blend provides clean energy.
• Regular use supports more efficient energy production at a cellular level, helping you maintain steady performance across long sessions and feel less fatigue at the end.
• Athletes and gym goers will benefit from natural performance support.

Peak O2 brings together Cordyceps, Reishi, Lion's Mane, Chaga, Turkey Tail and Maitake in a transparent six mushroom blend that’s USDA Organic certified and produced to GMP standards. The adaptogenic mix helps the body uptake oxygen more efficiently during workouts, while antioxidants support stress buffering and ATP production at a cellular level. Quality is our hallmark: each batch is tested for heavy metals and contaminants. This care mirrors the high standards you expect in skincare and cosmetics, and even in the world of valentino perfume.

Peak O2 (Cordyceps (Cordyceps militaris) Reisi (Ganderma Lucidum), King Trumpet (Pleurotus Eryngii), Shiitake (Lentinula Edodes), Lions Mane (Hericium erinaceus), Turkey Tail (Trametes Vericolor))

• GTIN: 5056371006108
• Manufacturer: Chemical Warfare
• Categories: Bodybuilding SupplementsCHECKOUT UPSELLNew ArrivalsNew In Supplements & Vitamins
• Best buy: 6 - 24 months+

United Kingdom Shipping:

Orders placed by 2pm (Monday to Friday) are dispatched the same day. Orders placed after 2pm will be dispatched the next working day.

Free shipping on orders over £50 to the UK.

Returns: Our products are meant to make you feel healthy and at your best. If you need to return your item, you can do so free of charge within 30 days in the same original and unopened packaging. Subject to T&C's.

Please consult the product packaging for accurate instructions on how to use the product.

Cordyceps is a natural medicine mushroom used to help energy metabolism and stamina. This ingredient sits inside a six-m mushroom blend that’s grown and certified organic for quality and purity.

This form comes from organic-certified mushrooms, and the blend stresses sourcing integrity and sticking to organic standards.

What Does Cordyceps Do?

Cordyceps participates in improving oxygen utilisation and endurance during exercise, with research suggesting enhanced aerobic and anaerobic performance and delayed fatigue in trained individuals, and this is something a lot of people notice when they push hard and stay in the zone.

The mix in Peak O2 also contains other mushrooms, which help to support the primary role of Cordyceps in oxygen uptake and stamina through antioxidant and energy-producing pathways, so you get a little boost and a steadier drive.

This product is not intended to diagnose, treat, cure, or prevent any disease.

Chemical Warfare is Welzo’s trusted partner for Peak O2 because their emphasis on a proven, organic mushroom blend lines up with our commitment to transparent, top‑quality sourcing. This brand has established itself as a specialist in adaptogenic mushroom formulations, bringing solid know‑how in mixing six organic-certified mushrooms to support oxygen use during exercise.

This brand's manufacturing excellence is underpinned by GMP standards and USDA Organic certification, with third‑party testing for contaminants and purity that reinforce trust in every batch. The adherence to recognised quality frameworks is a cornerstone of why we partner with Chemical Warfare, and it is reinforced by rigorous identity checks at the ingredient level. Our medical team our medical team evaluated this brand for compliance with the certifications we require, and confirmed their commitment to safety and quality.

Welzo endorses Chemical Warfare Peak O2 because the brand’s commitment to quality, transparency and science‑led formulation directly benefits customers seeking reliable performance support.