How long does diazepam take to work? Diazepam will work quite quickly or more slowly depending on what you’re taking it for:
- fits – diazepam rectal tubes should start to work within 10 minutes.
- anxiety – you should start to feel a bit better within a few hours, but it may take a week or two for you to feel the full effects.
- muscle spasms – you should begin to feel less pain after 15 minutes. Your muscles will start to relax when you have been taking diazepam regularly for a few days
8. Cautions with other medicines
Some medicines interfere with the way diazepam works and increase the chances of you having side effects.
Before you start taking diazepam, tell your doctor if you’re taking :
- antipsychotics used to treat mental health problems
- antidepressants used to treat depression
- anticonvulsants used to treat epilepsy
- hypnotics used to treat anxiety or sleep problems
- drowsy or sedating antihistamines, such as chlorphenamine or promethazine
- strong painkillers, such as codeine, methadone, morphine, oxycodone, pethidine or tramadol
- HIV medicines, such as ritonavir, atazanavir, efavirenz or saquinavir
- antifungal medicines, such as fluconazole
- proton pump inhibitors (PPIs) – medicines for reducing stomach acid, such as omeprazole or esomeprazole
- muscle relaxants, such as baclofen and tizanidine
- disulfiram, a medicine for alcohol addiction
- isoniazid, a medicine for tuberculosis
- rifampicin, a medicine for bacterial infections
- theophylline, a medicine for asthma and other breathing problems
Mixing diazepam with herbal remedies or supplements
There’s very little information about taking herbal remedies and supplements with diazepam.
Do not take herbal medicines for anxiety or insomnia, such as valerian or passionflower, with diazepam.
They can increase the drowsy effects of diazepam and may also have other side effects.