What Are the Risks of Mixing Valium With Other Substances?

A good rule is to always talk to a doctor before taking Valium in combination with any drug, herbal supplement, or vitamin. 

How Does Valium Work?

The biomechanics of how Valium works, at a technical level, are fairly complex. In essence, Valium is a benzodiazepine, which is a class of drug that acts on benzodiazepine receptors in the central nervous system. This interaction helps to slow abnormal activity in the brain. 

This is how Valium (which is a brand name for the drug diazepam) can help to relieve anxiety, reduce agitation in people going through alcohol withdrawal, and treat various types of muscle spasms and spasticity issues. 

What Substances Should Not Be Mixed With Valium?

There are several substances one should not mix with Valium without explicitly confirming it with a doctor and discussing the risks involved. Do not mix these with Valium:

• Muscle relaxants
• Anti-nausea medications
• Antihistamines
• Other benzodiazepines
• Barbiturates
• Alcohol
• Opioids
• CYP3A4 inhibitors like these:
  • Grapefruit juice
  • Clarithromycin
  • Itraconazole
  • Ketoconazole
  • Nefazodone
  • Ritonavir

Generally, it is best to talk with a doctor before mixing Valium with any drug (including both medicinal drugs and recreational drugs), herbal supplement, or vitamin. Special attention should be paid to any substance known to cause respiratory depression, which Valium can also cause. This type of combination may lead to a dangerous stacking of effects, discussed more below.

Why Is Drug Mixing So Potentially Dangerous?

One major concern when mixing any substance with Valium is that you may enhance its ability to depress respiration. In other words, Valium can weaken the muscles necessary to breathe. Used as prescribed, this isn’t usually dangerous. 

However, if abused or if mixed with the wrong substances, one can cause significant enough respiration that the body may struggle to get enough oxygen to the brain. This has the potential to cause a person to experience a variety of issues, including feeling extremely confused or losing consciousness. In severe cases, it can cause permanent brain damage or death. 

Valium is also a sedative and can cause drowsiness. If taken with another substance that can also cause drowsiness or otherwise enhances Valium’s sedative qualities, it may make this effect too powerful. This has the potential to cause a person to be unable to stay awake (for reasons separate than those related to how respiratory depression can cause a similar phenomenon), even if losing consciousness would be dangerous, such as while driving. 

On a more basic level, mixing Valium (or any other drug) with substances that change how a prescribing doctor expects your medication to work means that you are essentially modifying your treatment. This could make your treatment less effective or cause an unexpected reaction between the substances that is difficult to predict.