# Telling your employer about your prescription

Source: https://medcannaindex.com/guides/telling-your-employer

There is no single rule. Start with your contract and your workplace's drug and alcohol policy, which may require you to declare medicine that could affect your work. A workplace drug test cannot tell prescribed cannabis from illegal cannabis, so it usually helps to tell occupational health or HR before any test. If your condition counts as a disability under the Equality Act 2010, your employer must make reasonable adjustments.

Whether to tell, what your employer can and cannot do about drug testing, and where your condition gives you rights at work.

The short version

- Start with your contract and your workplace's drug and alcohol policy. They decide most of what follows.

- A workplace drug test cannot tell a prescribed medicine from an illegal drug, so it usually helps if the right person knows before any test.

- If the condition you are treated for counts as a disability in law, your employer has duties towards you.

Check your contract and policy first

Many employers have a drug and alcohol policy, and some require staff to declare any medicine that could affect their work. This is most common where safety is involved, such as driving, operating machinery or working at height. Read the policy before you decide what to say, because it tells you who to tell and what is expected.

Drug testing at work

The government's guidance on testing says:

- "Employers have to have consent if they want to test for drugs." Usually this is through a health and safety policy in the contract or staff handbook.

- Employers should limit testing to employees who need to be tested, make sure tests are random, and not single out particular employees unless the nature of their job justifies it.

- "Workers cannot be made to take a drugs test but if they refuse when the employer has good grounds for testing, they may face disciplinary action."

If your workplace tests, a prescribed product containing THC can produce a positive result. Telling occupational health or HR beforehand, with a copy of your prescription or a letter from your clinic, means a positive result has an explanation on record before it happens.

Your condition and the Equality Act

You are disabled under the Equality Act 2010 "if you have a physical or mental impairment that has a 'substantial' and 'long-term' negative effect on your ability to do normal daily activities." Substantial means more than minor or trivial. Long-term means 12 months or more.

Where that applies, "employers must make reasonable adjustments to make sure workers with disabilities, or physical or mental health conditions, are not substantially disadvantaged when doing their jobs."

These rights attach to your condition. The sources below do not say that an employer must allow a particular medicine to be taken at work, and they do not override safety rules. What is reasonable depends on your job, so ask for a conversation about adjustments, for example your duties or hours while a new medicine settles.

Being fit for work

Whatever your employer knows, do not do safety-critical work if your medicine has left you drowsy or less alert. Ask your prescriber what to expect and whether timing your doses around work would help.

How to raise it

- Ask to speak to occupational health, or to HR, in confidence.

- Bring a copy of your prescription or a clinic letter that names the medicine and confirms it is prescribed.

- Explain how it is taken and what your prescriber has said about work and driving.

- Ask for what is agreed to be put in writing.

Where to get advice

For advice on your own situation, contact Acas, Citizens Advice or your trade union. This guide is general information, not legal advice.
Sources
Checked on 5 October 2026. Laws and official guidance change, so read the source before you rely on anything here.
- GOV.UK: Being monitored at work: drug testing
- GOV.UK: Definition of disability under the Equality Act 2010
- GOV.UK: Reasonable adjustments for workers with disabilities or health conditions
- Acas: contact and helpline

From MedCannaIndex. Fees and product details are as recorded there and should be confirmed with the clinic or pharmacy. This is not medical advice: which product is suitable, and how much, is for the prescribing specialist.