Skip to main content

Can I take Diazepam and Codeine together?

Drug interaction guide

Taking diazepam and codeine together can cause extreme sleepiness, dizziness, and severe breathing difficulties. In serious cases, this combination can lead to a coma or be life-threatening because it can cause you to stop breathing.

Poursuivre la lecture ci-dessous

Why this happens

Both medicines are 'central nervous system depressants'. This means they both slow down brain activity and the signals that tell your body to breathe. When taken together, their effects add up, making the impact on your breathing and alertness much stronger than if taken alone.

What you should do

You should only take these two medicines together if they have been specifically prescribed by the same doctor who is aware you are taking both. If you must take both, use the lowest dose possible for the shortest amount of time. Seek emergency medical help immediately if you experience extreme sleepiness, shallow breathing, or difficulty staying awake. Avoid alcohol completely while taking these medicines.

Poursuivre la lecture ci-dessous

Important precautions

Combined use with other sedatives or alcohol

Taking these medicines together, or with alcohol, significantly increases the risk of life-threatening breathing problems and extreme sleepiness. Avoid alcohol and do not take other sedating medicines unless specifically directed by your doctor.

Ultra-rapid metabolism (CYP2D6)

Some people turn codeine into morphine much faster than normal. If you experience extreme sleepiness, confusion, or shallow breathing, stop taking the medicine and seek urgent medical help. This is especially dangerous for breastfeeding mothers as it can cause fatal overdose in the baby.

Long-term use and dependence

These medicines are for short-term use only. Taking them for more than a few days can lead to physical addiction and withdrawal symptoms when you stop. Do not increase the dose or take them for longer than prescribed.

Food and drink warnings

Alcool

You must avoid drinking alcohol while taking these medicines. Both diazepam and codeine cause drowsiness and slow down your breathing. Alcohol significantly increases these effects, which can lead to dangerous levels of sedation, breathing difficulties, and loss of consciousness.

Grapefruit juice

Avoid drinking large amounts of grapefruit juice. Grapefruit contains compounds that can stop your body from breaking down diazepam properly. This can lead to higher levels of the medicine in your blood, increasing the risk of side effects like extreme sleepiness and poor coordination.

Caffeine (Coffee, tea, energy drinks)

Caffeine is a stimulant and can have the opposite effect of diazepam, which is a sedative. Consuming high amounts of caffeine may make diazepam less effective at treating anxiety or helping you sleep.

Poursuivre la lecture ci-dessous

Using other medicines

Taking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.

Clause de non-responsabilité

This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.

Poursuivre la lecture ci-dessous

Historique de l'article

Les informations contenues dans cette page sont rédigées et évaluées par des cliniciens qualifiés.

  • 24 janvier 2026 | Publié à l'origine
Vérification de l'éligibilité à la grippe

Demandez, partagez, connectez-vous.

Parcourez les discussions, posez des questions et partagez vos expériences sur des centaines de sujets liés à la santé.

vérificateur de symptômes

Vous ne vous sentez pas bien ?

Évaluez gratuitement vos symptômes en ligne

Inscrivez-vous à la newsletter destinée aux patients

Votre dose hebdomadaire de conseils santé clairs et fiables, rédigés pour vous aider à vous sentir informé, confiant et maître de la situation.

Veuillez saisir une adresse e-mail valide.

En vous abonnant, vous acceptez notre politique de confidentialité. Vous pouvez vous désabonner à tout moment. Nous ne vendons jamais vos données.