Safety and testing

Side effects and precautions

2 articles

CBD Oil Side Effects: Safety of Cannabidiol

Read about CBD oil side effects, potential risks and precautions discussed in this guide.

CBD Vape Side Effects: What Should You Know?

Explore reported side effects of CBD vaping, product types and comparisons with nicotine vaping.

Drug tests and laboratory reports

4 articles

Does CBD Show up on a Drug Test?

Wondering if CBD could make you fail a drug test? Learn what the science says about isolate, full-spectrum, and THC levels in common testing methods.

Does CBD Oil Show in a Drug Test? Avoid Testing Positive

A guide to CBD products, traces of THC and the questions raised by workplace and roadside drug testing.

What is COA?

Learn what a certificate of analysis contains, how to find a batch number and how to read CBD laboratory results.

Certificate of Analysis

Browse Harmony laboratory reports by product and strength, and open the original certificates of analysis.

Legal questions and travel

3 articles

Is CBD Oil Legal in the UK and EU?

An overview of the UK legal questions discussed for CBD oil, including product categories and THC content.

Can You Take CBD Oil on a Plane? Travel with CBD Oil

Explore the checks discussed before travelling with CBD oil, including destination rules, THC content and hand luggage.

Is CBD Vape Juice Legal in the UK? A Guide to the Law

A guide to the UK legal questions surrounding CBD vape liquids, cannabinoids and THC content.

Caffeine, alertness and other research

5 articles

CBD, Eye Health, and Eyesight: What New Cannabidiol Research Reveals

Discover what a 2025 clinical trial found about CBD and vision. Learn how short-term CBD use affects visual clarity, night vision, and optical quality.

CBD (Cannabidiol) and Performance: What Science Says About Focus, Alertness, and Daily Functioning

Is CBD safe for work, driving, and daily focus? A 2024 meta-analysis finds that CBD doesn’t impair performance - unlike THC. Discover what this means for you.

CBD and Caffeine: Can You Safely Combine Them? Here’s What Science Says

Curious about mixing CBD and caffeine? Discover what new research says about combining cannabidiol and coffee, including safety, effects, and tips for daily use.

Does CBD Affect Your Performance? Here’s What You Need to Know!

Results from the latest research answer the question whether CBD affects your alertness, memory or reaction time.

What Happens When CBD Meets Caffeine? A New Study Sheds Light

Imagine mixing your morning coffee with a dash of your favourite CBD oil. But what would happen? All the details are in our latest article.