How long does CBD take to work?

Sublingual CBD oil (held under the tongue) typically takes 15-45 minutes to take effect. CBD capsules and edibles take 1-2 hours. Effects generally last 4-6 hours.

Can I take too much CBD?

CBD is generally well-tolerated, even at high doses. However, very high doses may cause drowsiness, digestive upset, or dry mouth. There's no known lethal dose, but more isn't always better - find your minimum effective dose.

Should I take CBD in the morning or at night?

It depends on your goals. For sleep, take CBD 30-60 minutes before bed. For daytime anxiety or pain, take it in the morning or split your dose throughout the day. Some people take CBD twice daily.

Does CBD interact with medications?

Yes, CBD can interact with certain medications, particularly those metabolized by the liver's CYP450 enzymes. If you take prescription medications, especially blood thinners or anti-seizure drugs, consult your doctor before using CBD.

What's the difference between full-spectrum, broad-spectrum, and isolate CBD?

Full-spectrum contains all hemp compounds including trace THC (<0.3%). Broad-spectrum has multiple cannabinoids but no THC. Isolate is pure CBD only. Full-spectrum may provide enhanced effects due to the 'entourage effect.'

Cannabis

CBD Dosage Calculator

Calculate your ideal CBD dose based on body weight, condition, and product strength. Includes dosing guide for sleep, anxiety, and pain.

CBD Calculator

Calculate your ideal CBD dose based on body weight, condition, and product strength. Includes dosing guide for sleep, anxiety, and pain.

Body WeightEnter your body weight

Primary UseWhat are you primarily using CBD for?

Symptom IntensityHow intense are your symptoms?

CBD Product StrengthCBD concentration (e.g., 1000mg in 30mL = 33mg/mL)

mg per mL

Dropper SizeStandard dropper is 1mL

CBD affects everyone differently. Start with a lower dose and gradually increase until you find what works for you. CBD may interact with certain medications - consult your healthcare provider if you take prescription drugs. These statements have not been evaluated by the FDA.

Important Disclaimer

About This Calculator

CBD (cannabidiol) is a non-intoxicating compound from hemp that many people use for wellness purposes including sleep, stress, and discomfort. Finding the right dose is personal and depends on factors like body weight, the condition being addressed, and individual body chemistry.

How It Works

Enter your weight, select what you're using CBD for, and indicate symptom intensity. The calculator uses weight-based dosing guidelines to recommend a starting dose. Enter your product's CBD concentration to see how many droppers to take. Start low and adjust based on your response.

Frequently Asked Questions

Beginners should start with 10-20mg of CBD per day and gradually increase. This allows you to gauge your body's response. Many people find their optimal dose between 25-75mg daily.

Clinical Review

Dr. Igor I. Bussel, MD

Board-Certified Ophthalmologist

Dr. Igor I. Bussel is a board-certified ophthalmologist and fellowship-trained surgeon affiliated with the University of California, Irvine (UCI), the Gavin Herbert Eye Institute, and the UCI School of Medicine.

Last Updated: 2025-01-05

Sources & Guidelines

Medically Reviewed

Evidence-Based

Updated 2025-01-05

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References

Reviewed by: Cannabis Education Team (Wellness Specialist)

Last updated: 2025-01-05