Diazepam Interactions
What Are Drug Interactions
Drug interaction refers to the interaction between substances where one substance changes how another works in the body. This can change the absorption, effect, and efficacy of a medicine.
Diazepam is a medicine that acts on the brain and central nervous system as a result, slowing down the brain activity. So, it can interact with other medicines or substances that have the same effect and may lead to increased side effects. This may include increased sedation, reduced alertness, and may also slow down the breathing.
It is important for you to understand diazepam interactions before starting any treatment, especially if you are taking other medicines.
Common Interactions
Some interactions are more common especially with medicines or substances that work on the brain and central nervous system
Alcohol
One of the most important interactions you should know about is the diazepam-alcohol interaction. Combining alcohol with diazepam can remarkably increase its effects. Both of these act on the brain, and if taken together, they can cause increased sleepiness, reduced coordination, and slower responses.
There are cases in which this combination may affect breathing and also increase the risks of accidents and injury. Hence, alcohol is best avoided when taking diazepam.
Opioids
Opioids are commonly used to relieve moderate to severe pain, but they also act on the nervous system and slows it down. When taken with diazepam, this effect can become more noticeable, leading to increased drowsiness and, in some cases, slower breathing.
Hence, this combination carries an increased risk of serious side effects, especially at higher doses. It may still be used in some situations, but only under close medical supervision.
Antidepressants
There are antidepressants that can interact with diazepam depending on how they act on the brain and how the body processes them. This can also increase drowsiness or affect coordination. In some cases, antidepressants may also affect the absorption of diazepam and alter its efficiency.
This interaction depends on the type of antidepressant, so, it is important that you inform your doctor about any medicines that you are taking.
Other medicines
There is a list of medicines that may affect the way diazepam works and increases the chances of side-effects. These may include, antipsychotics, anticonvulsants, hypnotics, antihistamines, HIV medicines, antifungals, PPIs, muscle relaxants, disulfiram, etc.
Before you take diazepam, you should inform your healthcare professional if you are taking any medicines even those that obtained without a prescription.
Food Interactions
Diazepam can be taken with or without food as recommended by your healthcare professional. However, there are few points to be taken care of.
- Herbal products and supplements such as valerian or passionflower, if taken along with diazepam, can increase its drowsy effects and other side effects.
- Grapefruit juice may increase the amount of diazepam in your blood.
- Drinks containing caffeine may reduce the effects of diazepam.
So, you should mention any supplements or herbal remedies you are taking while discussing about treatment with diazepam.
Why Interactions Can Be Dangerous
Drug-drug interactions or drug-food interactions can affect how strongly diazepam acts or for how long will it stay in the body. This may lead to symptoms discussed above which can interfere with daily activities and increase the risk of falls or accidents.
When diazepam is combined with other sedatives, this impact can be more serious and may even slow down breathing. Certain age groups such as older adults, people with a medical history, or if you are taking multiple medicines, may be more sensitive to these changes.
As diazepam stays in the body for an increased period of time, these effects can persist, especially with repeated use. Therefore, it is important to avoid combinations that may increase sedation or affect breathing.
How to Avoid Risks
Many risks related to interactions can be avoided with a few simple precautions. These can include keeping your healthcare provider informed about all the medicines you take, including non-prescription medicines and supplements. By doing this, potential interactions can be identified early.
Sticking to the prescribed dosage and avoiding making any changes to it without medical advice is very important. Alcohol can increase the effects of diazepam; hence, it is best avoided.
If you are starting with a new medicine, notice the way your body responds. Increased sleepiness, coordination changes, or any other unusual symptom may indicate an interaction. If you feel anything concerning or different, you should discuss it with your GP/doctor and seek medical care.
Knowing about drugs to avoid with diazepam and understanding about interactions can help reduce the risks and support a safe use.
Disclaimer
This information is based on the UK clinical guidelines and patient information leaflets and is to give a general understanding and what you might expect while taking it.
This content does not replace any medical advice, diagnosis, or treatment. If you have any concerns about your health, please seek advice from a licenced and qualified healthcare professional.
References
- Electronic Medicines Compendium, Diazepam Patient Information Leaflet, https://www.medicines.org.uk/emc/files/pil.101911.pdf [accessed 1 May 2026].
- National Health Service, Taking Diazepam with Other Medicines and Herbal Supplements, https://www.nhs.uk/medicines/diazepam/taking-diazepam-with-other-medicines-and-herbal-supplements/ [accessed 1 May 2026].
- National Health Service, About Diazepam, https://www.nhs.uk/medicines/diazepam/about-diazepam/ [accessed 1 May 2026].
- British National Formulary, Diazepam, https://bnf.nice.org.uk/drugs/diazepam/ [accessed 1 May 2026].
- DrugBank Online, Diazepam (DB00829), https://go.drugbank.com/drugs/DB00829 [accessed 1 May 2026].