Diazepam side effects

Diazepam is a sedative medication of the benzodiazepine class, prescribed for anxiety, seizures, fits and muscle spasms. It’s also used in hospitals to ease alcohol withdrawal and as a surgery preparation drug. It’s also commonly known by its brand name, Valium. Diazepam is prescription only and most commonly prescribed as 2, 5 or 10mg tablets, but can be obtained in liquid form or in a tube to be taken rectally.

Diazepam and other related drugs with similar effects, such as Z-drugs, totalled 14 million prescriptions in the UK as of 2017. This has led to concerns that diazepam is overprescribed, particularly among older people. Despite the NHS stating that diazepam should not be prescribed for more than four weeks, some people are on long-term prescriptions of diazepam, which contravenes NHS guidelines.

How diazepam works

Diazepam’s calming, sedative and anticonvulsant effects come about from its effect on the nervous system, specifically from its targeting of the brain’s gamma-aminobutyric acid (GABA) receptors. GABA’s main function is to inhibit neuronal activity – it calms the brain. Diazepam amplifies GABA’s calming effect on the brain, making it very useful for treating sleep disorders, anxiety and seizures – in the short term.

Diazepam usage becomes problematic when it’s used long-term, as the body habituates to it and tolerance develops.

Neuronal excitability

Neurons that are calmed by the amplified effect of GABA over a prolonged period become used to this calming effect and adapt. This means that these neurons are more sensitive and excitable when the drug is discontinued. This is why diazepam is only recommended for four weeks – it runs the risk of making the underlying conditions it’s treating worse in the long run, leading to heightened anxiety, insomnia and seizures when it’s stopped. This can be extremely dangerous, even fatal, and medical detox can be necessary.

Addictive potential

Diazepam’s calming effects, especially for anxious people, can cause addiction. Because of the rebound effects of diazepam, discontinuing it can be extremely unpleasant, and this can also exacerbate addiction. Tolerance builds very rapidly – potentially within seven days. If diazepam is no longer working due to tolerance, it is important only to take it as directed and not increase the dosage, as tolerance and dependence can occur rapidly.

As well as this, diazepam can indirectly increase dopamine in the brain’s reward pathways, which is a common way addiction manifests in the brain. GABA has an inhibitory effect on dopamine, which diazepam reduces, and this means diazepam can be experienced as pleasurable and rewarding, increasing its addictive potential.

Side effects of diazepam

While diazepam is generally well-tolerated when taken as directed, it does have side effects. Common side effects of diazepam are related to its sedating effects, including shakiness, difficulty with coordination, and lessened muscle control.

Diazepam has a long list of less common side effects, ranging from relatively benign (cough, sweating) to concerning (outbursts of anger, agitation, excessive movement – known as the paradoxical effects) to extremely serious, like seizures or vomiting.

Researchers aren’t sure why paradoxical reactions occur. Benzodiazepines calm the nervous system, but in rare cases (1-2%), they have the opposite effect, which can lead to rage, violent behaviour and assault, particularly after being taken intravenously. This is more frequent in anxious or aggressive individuals, children and the elderly.

Diazepam addiction

Continued use of diazepam and other benzodiazepines can lead to both physical and mental dependence. Diazepam addiction signs include developing a tolerance, experiencing withdrawal symptoms, and taking more of the drug to stave off withdrawal. Cravings, drug-seeking behaviour, and neglecting personal responsibilities are also common.

Taking diazepam consistently for more than four weeks is likely to lead to dependence, which requires tapering to manage. Withdrawal symptoms are unpleasant, meaning you may find it difficult to come off diazepam, especially if you have been taking it for a long time at high doses.

Diazepam abuse can lead to serious withdrawal symptoms, and medically assisted detox may be necessary. Some of the more serious side effects include hallucinations, agitation and seizures, which can be life-threatening. However, even if your diazepam usage hasn’t been heavy enough to cause serious withdrawal symptoms, they can still be hard to deal with and prolong efforts to withdraw from the drug. Because many of these symptoms mimic the things that people take diazepam for in the first place, like anxiety and insomnia, this can be particularly hard to deal with.

Diazepam interactions

Diazepam is particularly dangerous when mixed with other downers and significantly increases the risk of overdose. While diazepam dependency is dangerous, diazepam overdose from taking it alone is rare – although not impossible. However, when mixed with other sedating drugs, the central nervous system depression can result in death.

Diazepam isn’t just risky when mixed with powerful downers such as alcohol or opioids. The National Institute for Health and Care Excellence (NICE) lists 143 prescription medications that interact with benzodiazepines. Many drugs prescribed for a wide variety of conditions are capable of causing sedation. As well as central nervous system suppression, mixing these drugs can cause memory loss or increase the risk of getting into accidents.

As well as the dangers of mixing diazepam with downers, mixing them with uppers can be dangerous. Mixing drugs with opposite effects sounds counterproductive, but in addition, it’s quite common. Some people use them together to self-medicate for different things – downers are used to self-medicate for anxiety and low mood, with uppers used to counteract sedation. Some people enjoy the high that mixing two classes of drugs creates.

There is a mistaken belief amongst some that taking uppers and downers together counteracts the risk of overdose, but this isn’t true. Mixing these substances can mask the symptoms of overdose.

When to seek medical and professional help

Diazepam dependence is serious, and the withdrawal symptoms are unpleasant. If you find yourself developing a tolerance, experiencing withdrawal symptoms or mixing it with other substances to obtain enhanced effects, it’s important to reach out for support.

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