Marijuana Cannabis (Weed) Drug Test in California

A marijuana (cannabis) drug test checks for evidence of recent cannabis use. It is ordered when a person needs screening for medical, legal, or workplace reasons, or when a clinician is evaluating symptoms that may relate to cannabis.

What it measures

THC (tetrahydrocannabinol) — The main psychoactive substance in cannabis; its presence suggests recent use.
THC-COOH (carboxy-THC) — A breakdown product of THC that stays in the body longer and is often the target of testing.
11-OH-THC — Another THC breakdown product that can appear shortly after use.

Who it is for

Employers, legal authorities, or clinicians may order this test. It is not a routine medical test and is typically done only when there is a specific reason.

Preparation

No fasting or special preparation is needed. Tell the person drawing your blood about any prescription or over-the-counter drugs you take, as some can affect the result.

Results and what they mean

Results are usually reported as positive (cannabis compounds detected) or negative (not detected), sometimes with a numerical level. A positive result does not by itself mean impairment or a diagnosis; only a qualified clinician can interpret the findings in context. This information is general and not medical advice.

Requesting the Marijuana Cannabis (Weed) Drug Test in California

Order online, choose a certified collection site in California, and review results through a secure portal. No referral is required, and orders are processed confidentially. With coastal metros, inland towns, and rural counties with very different access to testing, it pays to schedule your collection in advance.

Frequently asked questions

How long does cannabis stay detectable in blood?

Detection time varies widely based on how often and how much a person uses, as well as individual body factors. Blood tests generally detect recent use better than long-term past use.

Can secondhand smoke cause a positive result?

Secondhand exposure is unlikely to cause a positive result on a standard blood test, but very heavy exposure in an enclosed space could potentially lead to a low-level detection.

Is this test confidential?

Yes, your test results are private and protected by law. They are shared only with those you authorize or as required by law.

What should I do if my result is positive?

Discuss the result with your healthcare provider. They can help you understand what it means for your health and any next steps.

Marijuana Cannabis (Weed) Drug Test by city in California

All testing in California → Full Marijuana Cannabis (Weed) Drug Test guide →