Valium and Xanax are two extremely popular benzodiazepine medications prescribed for the treatment of numerous medical conditions, most notably, generalized anxiety disorder and panic disorder. Occasionally, Xanax and Valium are prescribed on a short-term basis for the management of alcohol withdrawal or opioid detoxification.
Of these two benzodiazepines, Valium is the “older” medication that hit the market in 1963, whereas Xanax is somewhat “newer” in that it hit the market in 1981. Valium was developed by chemists at Hoffmann-La Roche, whereas Xanax was developed by chemists at Upjohn (now merged with Pfizer Inc.).
Valium vs. Xanax (Comparison Chart)
Included below is a chart that highlights similarities and differences between Valium (Diazepam) and Xanax (Alprazolam). If you have specific questions about commonalities and/or differences between these benzodiazepines, it is recommended to consult a medical doctor and/or pharmacist.
|Approved medical uses||Anxiety disorders (short-term). Alcohol withdrawal (agitation, tremor, delirium tremens, hallucinosis).||Generalized anxiety disorder. Panic disorder.|
|Adjunct uses||Skeletal muscle spasms. Spasticity (associated with upper motor neuron disorders). Convulsive disorders.||Chemotherapy-induced nausea and vomiting.|
|Average duration of use||Less than 4 months.||Up to 8 months.|
|Bioavailability||~76% (oral)||~90% (oral)|
|Formats||Tablet. Oral solution. Vial.||Tablet. Extended-release (XR or ER) pill. Oral disintegrating tablet. Oral solution.|
|Dosages||Tablet: 2 mg, 5 mg, 10 mg|
Oral solution: 120 ml 5mg/5ml
|Tablet: 0.25 mg, 0.5 mg, 1 mg, 2 mg|
Oral disintegrating tablet: 0.25 mg, 0.5 mg, 1 mg, 2 mg
Extended-release (XR) pills: 0.5 mg, 1 mg, 2 mg, 3 mg
Oral solution: 30 ml 1 mg/ml
|Manufacturer||Hoffmann-La Roche||Pfizer Inc. (Upjohn)|
|Legal status||Schedule IV (U.S.)||Schedule IV (U.S.)|
|Mechanism of action||GABAA receptor positive allosteric modulator (PAM).|
Acts within the limbic system, thalamus, and hypothalamus.
Increases inhibitory activity throughout the cerebral cortex.
Acts as a voltage-gated sodium channel (VGSC) modulator to induce anticonvulsant effects.
Exerts a myorelaxant effect by inhibiting polysynaptic pathways in the spinal cord.
|GABAA receptor positive allosteric modulator (PAM). |
Suppresses activity within the HPA (hypothalamic-pituitary-adrenal) axis.
Increases extracellular D1 and D2 dopamine concentrations in the striatum.
|Generic version (?)||Yes.||Yes.|
|Half-Life||36 to 50 hours||9 to 16 hours|
|Common side effects||Drowsiness. Fatigue. Muscle weakness. Ataxia.||Drowsiness. Lightheadedness. Dry mouth. Depression. Headache. Constipation. Diarrhea.|
|Duration of effect||4 to 6 hours||Standard: ~5 hours|
Extended-release: ~11 hours
|Metabolism||Hepatic: CYP2C19. CYP2D6. CYP2B6.||Hepatic: CYP3A4.|
Valium vs. Xanax: What are the major differences?
Major differences between Valium and Xanax include: FDA-approved uses; routes of metabolism (in the body); available formats; half-life; side effects; and discontinuation symptoms. Based on chemical structure, Valium differs from Xanax in that Valium is a standard “benzodiazepine,” whereas Xanax is a “triazolobenzodiazepine.”
As a triazolobenzodiazepine, Xanax contains an additional fused triazole ring – relative to Valium. Although both Xanax and Valium are FDA approved for the management of anxiety disorders, Valium is also indicated for the treatment of acute alcohol withdrawal symptoms and muscle spasms (Xanax is not) – whereas Xanax is indicated for the management of panic disorder (Valium is not).
Valium is available in formats of tablets, oral solution, and vials – whereas Xanax is available in a variety of formats, including: standard immediate-release tablets, extended-release (XR) pills, oral disintegrating tablets (ODT), and oral solution. Xanax users have a greater number of formats to select from – which some might consider an advantage.
In terms of metabolism, Valium and Xanax are metabolized differently within the body. Valium is metabolized in the liver by CYP2C19 and CYP2D6 enzymes and, to a lesser extent, CYP2B6 – whereas Xanax is metabolized in the liver by CYP3A4 enzymes. Differences in routes of metabolism might make one drug more effective than the other – as a result of a user’s gene expression.
The half-lives of Valium and Xanax differ significantly in that Valium exhibits an elimination half-life of 20 to 100 hours, yet Xanax exhibits an elimination half-life of 4 to 6 hours (immediate-release) and 10.7 to 15.8 hours (extended-release). This means that Valium stays in your system for a much longer duration than Xanax stays in your system.
The onset of effect for Valium is documented as being 2 to 3 minutes, whereas the onset of effect for Xanax is suggested as being ~1 hour (in some cases). Though the duration of effect is similar between standard Valium and Xanax (~4 to 6 hours), the extended-release Xanax can exert an effect for up to ~11 hours.
Fatigue, muscle weakness, and ataxia are more likely to occur as side effects of Valium, whereas lightheadedness, dry mouth, depression, headache, constipation, and diarrhea are more likely to occur as side effects of Xanax. While there may be some differences between Valium and Xanax – the medications are very similar in terms of: mechanism of action; clinical efficacy; legal status; and cost.
As benzodiazepines, both Valium and Xanax have a high addiction potential; benzodiazepines (as a class) are regarded as being among the most addictive drugs in the world. Both Valium and Xanax are efficiently absorbed following administration and rapidly enter the brain to enhance GABAergic transmission and suppress CNS activity (usually within minutes).
Additionally, a downstream effect of GABAA receptor subunit modulation is a reduction in the firing rate of inhibitory interneurons throughout the ventral tegmental area (VTA) of the brain. Reduced firing rates of inhibitory interneurons in the ventral tegmental area (VTA) leads to reductions in the firing rates of dopamine-secreting neurons, which in turn, increases dopamine in the extracellular space – inducing a euphoriant effect among benzodiazepine users.
It is the rapid onset of anxiolytic, myorelaxant, and euphoriant effects that makes both Valium and Xanax addictive with significant abuse potential. According to Juergens (1991), the rapid absorption of benzodiazepines induces psychological reinforcement which might lead to benzodiazepine overuse disorder or addiction.
Due to its popularity, shorter half-life, and harsher withdrawal – a case could be made that Xanax is more addictive than Valium. Nevertheless, both medications act similarly within the brain and are classified as “Schedule IV” substances in the United States – indicating potential for psychological and/or physical dependence.
Approved medical uses
Both Valium and Xanax are approved by the United States FDA for the treatment of anxiety disorders (e.g. generalized anxiety disorder) – and for the short-term (acute) management of anxious symptoms. Valium is also approved by the FDA for the management of symptoms associated with alcohol withdrawal or detoxification such as: agitation, tremor, delirium tremens, and hallucinosis (Xanax is not) – whereas Xanax is also approved by the FDA for the management of panic disorder (Valium is not).
Occasionally, Xanax might be prescribed off-label (instead of Valium) to help counteract alcohol withdrawal symptoms, whereas Valium might be prescribed off-label (instead of Xanax) to help manage panic disorder. Unlike Xanax, Valium is commonly administered as an adjunct treatment for spasticity (due to motor neuron disorders) and convulsive disorders.
However, unlike Valium, Xanax is commonly used as an adjunct for the treatment of chemotherapy-induced nausea and vomiting. Each of these medications (Valium and Xanax) are sometimes prescribed off-label to attenuate symptoms of neuropsychiatric conditions like: PTSD, social phobia, insomnia, premenstrual syndrome, and agitation.
Cost: Which is more expensive?
Both Valium and Xanax are similarly-priced when sold as generics Diazepam and Alprazolam, respectively. Attaining 60 tablets of generic Valium (Diazepam) costs between $7.55 and $15 (on average), whereas attaining 60 tablets of generic Xanax (Alprazolam) costs between $7.75 and $21 (on average).
- Valium tablets (generic): $7.55 to $15 (60 tablets)
- Valium standard (brand): $212 to $577 (60 tablets) – The pricing for brand name Valium is dose-dependent in that lower doses (2 mg) cost less than larger doses (10 mg).
- Valium (vial): $23 to $46 (10 ml of 5 mg/ml)
- Valium (oral solution): $21 to $40 (1 bottle of 30 ml – 5 mg/ml)
- Xanax tablets (generic): $7.75 to $21 (60 tablets)
- Xanax standard (brand): $245 to $730 (60 tablets) – The pricing for brand name Xanax is dose-dependent in that lower doses (0.25 mg) cost less than larger doses (2 mg).
- Xanax ODT (orally disintegrating tablet): $29 to $82 (30 tablets)
- Xanax XR or ER (extended release): $16 to $67 (30 tablets) – The pricing for Xanax XR is dose-dependent in that lower doses (0.5 mg) cost less than larger doses (3 mg).
- Xanax (oral solution): $47 to $103 (1 bottle of 30 ml – 1 mg/ml)
Purchasing generic Valium tends to be slightly lower cost (on average) than purchasing generic Xanax, however, prices may vary among pharmacies. That said, most people probably won’t consider the prices of generics (Valium and Xanax) to be significantly different.
Although it is relatively uncommon for people to buy “brand name” Valium and Xanax (as generics are available), the brand name versions of each medication are relatively expensive. Buying 60 brand name Valium tablets will cost between $212 and $577 (on average), whereas buying 60 brand name Xanax tablets will cost between $245 and $730 – making Xanax the more expensive option.
A bottle of Valium oral solution (30 ml of 5 mg/ml) retails for $21 to $40, whereas a bottle of Xanax oral solution (30 ml of 1 mg/ml) retails for $47 to $103 – making Xanax the more expensive option. Unlike Xanax, Valium is available in a vial format that costs between $23 and $46 per vial (10 ml of 5 mg/ml).
However, unlike Valium, Xanax is available in the form of an orally disintegrating tablet that costs between $29 and $82 for 30 tablets – as well as in the form of an extended-release tablet (XR or ER) that retails for $16 to $67 for 30 tablets. Overall, the cost of Xanax is slightly more than the cost of Valium – regardless whether brand name vs. generic and the formatting.
Dosage & Formats
Valium and Xanax are each manufactured in the formats of immediate-release tablets and an oral solution. Immediate-release Valium tablets are sold in dosages of 2 mg, 5 mg, and 10 mg – and immediate-release Xanax tablets are sold in dosages of 0.25 mg, 0.5 mg, 1 mg, and 2 mg.
The oral-solution Valium format provides 30 ml of 5 mg/ml doses and the oral-solution Xanax format provides 30 ml of 1 mg/ml. These oral formats are considered useful for patients who are gradually titrating or tapering off of the medications because some individuals find it easier to measure dosages in liquid format rather than attempting to hassle with splitting pills.
Valium differs from Xanax in that it is manufactured in the format of vials for injection. Xanax differs from Valium in that it is manufactured in the formats of an orally-disintegrating tablet (ODT) and an extended-release tablet.
The orally-disintegrating tablet (ODT) format of Xanax is convenient in that it dissolves when placed in the mouth (on the tongue) and doesn’t need to be swallowed whole. Additionally, the extended-release (XR or ER) format of Xanax is convenient in that it delivers an effect for around ~11 hours (this is nearly double the duration of standard Valium and standard Xanax).
If patients prefer to use orally-disintegrating tablets (ODT) or extended-release tablets, then Xanax may be perceived as a better option than Valium (which isn’t available in those formats). On the other hand, if an injectable vial is preferred, then Valium may be perceived as a better option than Xanax (which isn’t available in vial format).
Effectiveness: Which medication is more effective?
Based on the scientific literature, there’s no strong evidence to suggest that Valium is more effective than Xanax (or vice-versa) for the treatment of anxiety disorders. A study by Noyes et al. (1996) involving 241 patients with panic disorder or agoraphobia with panic attacks were assigned to receive Valium, Xanax, or a placebo for 8 weeks.
At the end of the 8-week period, over 60% of patients receiving Valium or Xanax were “moderately improved” – compared to just 30% of patients receiving a placebo. Measures of revealed that Valium and Xanax were equally effective and tolerable for the treatment of panic disorder.
A comparative trial conducted by Davison et al. (1985) involving 46 patients with anxiety reported significant reduction in anxious symptoms after a 28-day treatment period – regardless of whether Valium or Xanax was administered. This trial supports the idea that Valium and Xanax are of similar efficacy for the management of anxiety disorders.
That said, the trial reported Xanax as being significantly more effective than Valium and a placebo in reducing symptoms of depression (as was measured via the Hamilton Anxiety Rating Scale and Hamilton Depression Rating Scale). Based on the results of this trial, one might speculate that Xanax may be a superior intervention for “anxious depression” than Valium, however, no strong conclusions can be made due to the fact that this was one (small-scale) study.
A 4-week double-blind study by Elie and Lamontagne (1984) comparing the effectiveness of Xanax and Valium in 48 patients with generalized anxiety (mild-to-moderate) reported that Valium was “more efficient” than Xanax in counteracting several symptoms of anxiety and depression. Specifically, Valium controlled symptoms of anxiety at a quicker rate than Xanax, and appeared better at reducing depressive symptoms. Nevertheless, researchers stated that neither medication was more effective in the treatment of generalized anxiety disorder – and there were no clinically-relevant differences between the two medications.
Earlier research by Maletzky (1980) compared the anxiolytic effects of Xanax (0.5 mg to 3 mg), Valium (5 mg to 60 mg), and a placebo – in 86 patients with psychoneurotic anxiety (moderate-to-severe) over a 28-day period. Results of the study revealed that Xanax was more effective than Valium on several measures of effectiveness – and more effective than the placebo in all measures of effectiveness.
In summary, multiple studies suggest that Valium and Xanax are of equal efficacy, 1 study suggested that Xanax might be superior for “anxious depression,” 1 study suggested that Valium might be superior in onset of action (“kicking in” faster) and for “anxious depression,” and 1 study discovered that Xanax was more effective than Valium on several measures of anxiety including the Hamilton Anxiety Rating Scale (HARS), two Physician’s Global Impression scores, Patient’s Global Impressions, and Target Symptoms.
Because data are mixed, most medical professionals regard Valium and Xanax as being of clinically-equivalent efficacy for the management of anxiety disorders and acute anxiety. Considering the FDA-approved uses (i.e. indications) of each medication, it’s reasonable to hypothesize that Valium might be superior to Xanax for the management of alcohol withdrawal, whereas Xanax might be superior to Valium for the management of panic disorder.
Additionally, reflecting upon FDA-approved adjunct uses, it’s fair to hypothesize that Valium might be superior to Xanax for the treatment of skeletal muscle spasms, spasticity, and convulsive disorders – whereas Xanax might be superior to Valium for the treatment of chemotherapy-induced nausea and vomiting. Nevertheless, because the medications haven’t been directly compared in large-scale randomized controlled trials for the treatment of specific medical conditions – no definitive conclusions can be made as to whether one drug is of superior efficacy versus the other.
- Source: https://www.ncbi.nlm.nih.gov/pubmed/8752017
- Source: https://www.ncbi.nlm.nih.gov/pubmed/2859877
- Source: https://www.ncbi.nlm.nih.gov/pubmed/6145726
- Source: https://www.ncbi.nlm.nih.gov/pubmed/6102940
Mechanism of action
Pharmacodynamic assessments of Valium and Xanax suggest that these medications exhibit similar mechanisms of action. Both Valium and Xanax function principally as positive allosteric modulators (PAM) of the GABAA receptor whereby they potentiate the binding of the major inhibitory neurotransmitter “GABA” (gamma-aminobutyric acid) to the GABAA receptor.
GABAA receptors are located throughout the CNS and are comprised of 5 protein subunits (2-alpha, 2-beta, and 1-gamma). Normally, without the presence of a benzodiazepine, the neurotransmitter GABA will bind weakly to the alpha subunit of the GABAA receptor, allowing negatively-charged chloride ions to enter the neuron.
When Valium or Xanax is administered, each medication allosterically binds to the gamma subunit of the GABAA receptor, causing the neurotransmitter “GABA” to bind to the alpha-subunit more efficiently. As a result, more negatively-charged chloride ions enter the neuron and induce a state of hyperpolarization (the inside of the neuron is more negatively charged than the outside of the neuron.
As a result, the neurons become inhibited such that they aren’t as responsive to stimulation from excitatory postsynaptic potentials – and activity throughout the central nervous system (CNS) is suppressed. It is this mechanism of action that alleviates psychological and physical symptoms of anxiety such as racing thoughts and muscle tension.
Though the primary mechanisms of action associated with Valium and Xanax are similar, there may be subtle differences in other actions. Valium has been suggested to exert a pronounced effect within the limbic system, thalamus, and hypothalamus and appears to act as a voltage-gated sodium channel (VGSC) modulator to induce anticonvulsant effects.
Furthermore, Valium exerts a myorelaxant effect via suppressing activity in polysynaptic pathways throughout the spinal cord. Xanax has been suggested to exert a pronounced effect within the hypothalamic-pituitary-adrenal (HPA) axis – and appears to increase extracellular D1 and D2 dopamine levels in the striatum.
Metabolism & Half-Life
The route of metabolism and elimination half-life differs substantially between Valium and Xanax. Valium is metabolized in the liver by the cytochrome P450 isoenzymes such as: CYP2C19, CYP2D6, and CYP2B6 – whereas Xanax is metabolized in the liver by the cytochrome P450 isoenzyme CYP3A4.
The average elimination half-life range for Valium is 30 to 56 hours (~43 hours) and the average elimination half-life range for Xanax is 9 to 16 hours in healthy adults. That said, the full elimination half-life range for Valium is 20 to 80 hours and the full elimination half-life range for Xanax is 6.3 to 26.9 hours.
When Valium is metabolized, it forms nordiazepam as a pharmacologically-active major metabolite plus temazepam and oxazepam as minor metabolites. The elimination half-life of nordiazepam is estimated as ranging from 40 to 100 hours.
When Xanax is metabolized, it forms metabolites such as: alpha-hydroxyalprazolam (alpha-OHALP) and 4-hydroxyalprazolam (4-OHALP); the former is more bioactive than the latter. Because the half-lives of Valium and its nordiazepam metabolite are considerably longer than Xanax and its metabolites, Valium is eliminated from the body at a much slower rate by comparison.
Valium was introduced in 1963, making it the second benzodiazepine to hit the United States market after Librium in 1960. Because Xanax wasn’t introduced until 1981, Valium was likely the most popular benzodiazepine throughout the 1960s, 1970s, and even 1980s (due to the fact that Xanax didn’t have a proven track-record for safety, efficacy, and tolerability when it was initially introduced).
However, as of 2018, Xanax is significantly more popular than Valium. According to the ClinCalc DrugStats database, over 27 million prescriptions were filled for generic Xanax (alprazolam) in 2018 – making it the 23rd most-prescribed pharmaceutical medication in the United States.
Comparatively, the ClinCalc DrugStats database reports that approximately 8.9 million prescriptions were filled for generic Valium (diazepam) in 2018 – making it the 91st most prescribed pharmaceutical medication in the United States. These data indicate that the number of Xanax prescriptions filled in 2018 were over three-fold the number of Valium prescriptions.
The most common side effects associated with Valium (according to FDA database data) include: drowsiness, fatigue, muscle weakness, and ataxia. The most common side effects associated with Xanax (according to FDA database data) include: drowsiness, lightheadedness, dry mouth, depression, headache, constipation, and diarrhea; each of these side effects occur in at least 10% of users.
Based on this data, it appears as though Valium causes fewer side effects than Xanax such that it may be easier to tolerate. Unlike Xanax, Valium may be less likely to cause lightheadedness, dry mouth, depression, headache, constipation, and diarrhea.
However, unlike Valium, Xanax may be less likely to cause fatigue, muscle weakness, and ataxia. Nevertheless, studies that have directly compared the tolerability of Valium and Xanax for the treatment of anxiety haven’t reported any clinically significant differences.
Moreover, due to the fact that Valium and Xanax exhibit similar mechanisms of action (as GABAA receptor positive allosteric modulators), side effects are relatively similar. That said, because there are more data regarding incidence rates of side effects associated with Xanax than Valium – it’s possible that Valium side effects are underrepresented on FDA packaging data.
- Source: https://www.accessdata.fda.gov/drugsatfda_docs/label/2016/013263s094lbl.pdf
- Source: https://www.accessdata.fda.gov/drugsatfda_docs/label/2011/018276s044,021434s006lbl.pdf
Discontinuation of Valium or Xanax can provoke harsh withdrawal symptoms, and a subset of long-term users will experience post-acute withdrawal syndrome (PAWS). Withdrawal symptoms are understood to emerge as a form of neurophysiologic recalibration to compensate for activity of the benzodiazepine.
Ongoing treatment with Valium or Xanax will induce neurophysiologic adaptations such as downregulation of GABAA receptors (due to regular stimulation) – whereby benzodiazepines or GABAA receptor modulators become necessary to maintain neurochemical balance. Upon discontinuation of Valium or Xanax, the former user’s neurophysiology is still expecting to receive the GABAergic effects of the medication.
Because GABAA receptor subunits have downregulated (as an adaptation to ongoing benzodiazepine treatment), neurochemical imbalances occur when Valium and Xanax treatment ends. Though the former user’s neurophysiology will attempt to transition back to homeostasis by inducing changes (such as by upregulating GABAA receptor subunits), these changes require time (e.g. days, weeks, or months).
During this transition, GABAA receptors won’t be sufficiently activated and excitatory neurotransmission will be excessive. In extreme cases, this excitatory neurotransmission could trigger harsh symptoms like seizures, panic attacks, hypertension, palpitations, and tachycardia.
For this reason, is always recommended to gradually discontinue Valium and Xanax with the help of a medical doctor – preferably a psychiatrist. That said, it is understood that Valium is generally easier for most people to discontinue due to the fact that it has a significantly longer elimination half-life than Xanax.
The half-life of Valium ranges from 20 to 80 hours and the half-life of its metabolite nordiazepam ranges from 40 to 100 hours, whereas the elimination half-life of Xanax ranges from 6.3 to 26.9 hours. The longer half-life of Valium means that the medication and its metabolites remain in the former user’s system for a longer duration following cessation.
Because diazepam and nordiazepam remain in the body for a long time after Valium is stopped, this allows the body to gradually readjust itself to functioning with less GABAA receptor modulation over an extended duration – allowing for a smoother transition back to homeostasis (and less of an excitatory backlash) relative to Xanax. In fact, some individuals attempting to withdraw from Xanax may transition to Valium for an easier discontinuation process.
Similarities (Recap): Valium vs. Xanax
Included below is a summary of the similarities between Valium and Xanax.
- Abuse potential: Both Valium and Xanax have a modest potential for abuse because each can induce a combination of anxiolytic and myorelaxant effects (via modulating GABAA receptors) and euphoriant effects (via facilitating the downstream release of extracellular dopamine). Moreover, because onset of action associated with Valium and Xanax is rapid, psychological reinforcement can occur. Valium and Xanax are sought out as “street” or “party drugs” for the sake of a recreational “high” (i.e. intoxication).
- Cost: The cost of generic Valium is relatively similar to the cost of generic Xanax. A total of 60 Diazepam (Valium) tablets sell for $7.55 to $15 and a total of 60 Alprazolam (Xanax) sell for $7.75 to $21. The standard brand name version of Valium retails for $212 to $577 (60 tablets), whereas the standard brand name version of Xanax retails for $245 to $730 (60 tablets). Though the average price of Valium is slightly less than Xanax – most would consider the prices to be similar for standard generic and brand name tablet formats.
- Drug classification: Valium and Xanax are classified as “benzodiazepines” because their core chemical structures consist of a benzene ring fused to a diazepine ring. As benzodiazepines, Valium and Xanax function by modulating the inhibitory neurotransmitter “GABA” within the brain.
- Duration of effect: The duration of effect for standard Valium and Xanax tablets is similar. Standard Valium is estimated to exert an anxiolytic effect for ~4 to 6 hours (on average) and standard Xanax is estimated to exert an anxiolytic effect for ~5 hours (on average).
- Effectiveness: Both Valium and Xanax have proven to be more effective than placebos in large-scale randomized controlled trials for the treatment of anxiety disorders. Neither drug is considered superior in efficacy relative to the other for the management of acute anxiety and anxiety disorders.
- Generic availability: The patents for brand name Valium and Xanax have long expired and both drugs are available as generics. Generic Valium is sold under the name “Diazepam” in the form of tablets, vials, and oral solution – and generic Xanax is sold under the name “Alprazolam” in the form of tablets, extended-release pills, orally-disintegrating tablets, and oral solution.
- Legal status: Valium and Xanax are classified as “Schedule IV” substances in the United States. This classification indicates that the medications: (1) have a low potential for abuse relative to Schedule III substances; (2) have an accepted medical use; and (3) may induce limited physical and/or psychological dependence if abused.
- Mechanism of action: The mechanisms by which Valium and Xanax act within the brain are similar. Both medications function primarily as positive allosteric modulators (PAMs) of the GABAA receptor whereby they enhance the efficiency of GABA binding to alpha subunits of the GABAA receptor. This enables negatively-charged chloride ions to enter neurons and induce neuronal hyperpolarization for suppression of CNS activity.
- Medical uses: Valium and Xanax are FDA-approved for the treatment of anxiety disorders and acute symptoms of anxiety.
- Side effects: There is significant overlap in the side effects that can occur while using Valium and Xanax. The most common side effect of each medication is drowsiness – the feeling of being sleepy and lethargic. Each medication can induce confusion, muscle weakness, cognitive dysfunction, and motor impairment.
- Withdrawal: Withdrawing from Valium and Xanax can be extremely challenging for long-term users. Once a person’s neurophysiology has adapted to the effects of Valium or Xanax – stopping treatment can cause a compensatory physiologic response whereby withdrawal symptoms occur.
Differences (Recap): Valium vs. Xanax
Included below is a summary of some noteworthy differences between Valium and Xanax.
- Cost: Although cost may not differ much between standard brand name and generic Valium and Xanax tablets – cost is notably different for users of oral solution formats. One bottle (30 ml with 5 mg/ml) of oral Valium solution costs between $21 and $40 (on average) – making it cheaper than one bottle (30 ml with 1 mg/ml) of oral Xanax solution which costs between $47 and $103 (on average).
- Formats: Valium is manufactured in a vial format intended for injection, whereas Xanax is not. However, Xanax is manufactured in multiple formats that Valium is not, including: orally-disintegrating tablets (ODT) and extended-release pills (XR or ER).
- Half-life: The half-life of Valium is substantially longer than the half-life of Xanax. In healthy adults, the half-life of Valium falls between 30 and 56 hours – whereas the half-life of Xanax falls between 9 and 16 hours. Additionally, the primary biologically-active metabolite of Valium known as “nordiazepam” exhibits a half-life between 40 and 100 hours – whereas metabolites of Xanax exhibit half-lives shorter than the parent chemical.
- Ingredients: The active ingredient in Valium is the chemical “Diazepam” and the active ingredient in Xanax is “Alprazolam.”
- Manufacturers: Valium was developed by chemists at the company Hoffmann-La Roche – and Xanax was developed by chemists at Upjohn (now part of Pfizer Inc.).
- Medical uses & adjunct uses: Valium has received FDA approval for the management of alcohol withdrawal symptoms (whereas Xanax has not). Xanax has received FDA approval for the management of panic disorder (whereas Valium has not). Valium is more commonly utilized as an adjunct to treat skeletal muscle spasms, spasticity, and convulsive disorders – whereas Xanax is more commonly utilized as an adjunct to treat chemotherapy-induced nausea and vomiting.
- Metabolism: Valium undergoes hepatic metabolism via CYP2C19, CYP2D6, and CYP2B6 enzymes. Xanax undergoes hepatic metabolism via CYP3A4 enzymes.
- Popularity: As of 2018, Xanax is the most prescribed benzodiazepine in the United States with over ~27 million prescriptions filled throughout the year. Comparatively, as of 2018, just under ~8.9 million prescriptions for Valium were filled throughout the year.
- Withdrawal severity: Though both Valium and Xanax can induce withdrawal symptoms, Valium is generally regarded as an easier medication to discontinue. Withdrawal symptoms tend to be less severe when discontinuing Valium (as compared to Xanax) as a result of the longer half-life associated with Valium.
Which medication is better for anxiety disorders? (Valium or Xanax)
If you ask a medical doctor or psychiatrist as to whether Valium is better than Xanax – or if Xanax is better than Valium – you probably won’t get a definitive answer. This is because scientific research suggests that both Valium and Xanax are significantly more effective than a placebo for the treatment of acute anxiety and anxiety disorders – but there’s no convincing evidence to suggest that one medication is inherently superior (in terms of efficacy) when compared directly to the other.
There’s some evidence suggesting that Valium might take effect more quickly than Xanax, however, this is debatable. That said, persons who consult a medical doctor about using a benzodiazepine for the management of an anxiety disorder are more likely to receive a prescription for Xanax because: (1) it is manufactured in more formats than Valium (something patients may prefer); and (2) research suggests that Xanax can be administered for 4+ months for anxiety disorders (whereas the research is lacking for long-term Valium use).
Still, both Valium and Xanax are considered safe, tolerable, and effective medications for the treatment of anxiety when used in accordance with medical instruction. It’s likely that many people will respond equally well to Valium and Xanax – and it’s likely that a subset of the population will respond better to one drug (e.g. Valium) versus the other (e.g. Xanax).
Individuals who respond better to Valium over Xanax (or vice-versa) might carry certain genes that allow for better hepatic metabolism of one drug versus the other. For example, someone with CYP2C19 or CYP2D6 abnormalities (attributable to genetics) might metabolize Valium suboptimally and respond poorly to its effect, whereas someone with CYP3A4 abnormalities might metabolize Xanax suboptimally and respond poorly to its effect.
Preexisting neurochemistry, concurrent substance use, preexisting medical conditions, etc. – could all impact how well Valium and Xanax work. It may take some trial and error before you find the optimal benzodiazepine (or anxiolytic) for treating symptoms of anxiety.
If attempting to choose between Valium and Xanax, it is recommended to work closely with an experienced medical doctor and discuss the “pros” and “cons” of each medication. Maintaining a regular journal can help you understand the effectiveness of each medication (for your medical condition) over an extended period (e.g. 1 to 2 months).
My Personal Experiences Taking Valium & Xanax
In the past, used Xanax (“as needed”) for a period of around 3 years – both the standard (short-acting) tablets and the extended-release (XR) pills. From my subjective perspective, Xanax kicked in extremely fast (within minutes of ingestion) and worked extremely well for managing symptoms of social anxiety disorder, generalized anxiety disorder, and hypochondriasis.
However, Xanax was problematic in that caused substantial cognitive impairment and interfered with clarity of thought; my mind would go “blank” while speaking and writing. Additionally, I felt slightly dizzy, lightheaded, noticed a subjective decline in my hand-eye coordination, and slight exacerbation of depression while under the influence of Xanax.
Although I don’t have much experience using Valium, I was prescribed Valium once for the acute management of anxiety before and during an MRI scan. While under the influence of Valium, I felt extremely relaxed – probably more relaxed than while under the influence of Xanax, however, I cannot recall the dosage (it might’ve been a greater “relative” dose than Xanax – thus accounting for the heightened anxiolytic effect).
Similar to while under the influence of Xanax, I experienced cognitive impairment, “brain fog,” dizzy, lightheaded, and impaired motor performance – while under the influence of Valium. Although I did not experience exacerbation of depression while using Valium (like I did while taking Xanax), this could be due to the fact that I only used Valium once (rather than over an extended period).
Reflecting upon on my personal experience with each medication, Valium and Xanax were extremely effective for treating anxiety. I wouldn’t consider one medication to be of superior efficacy or tolerability (based on my experience) when compared to the other.
However, because I used Xanax intermittently over a long-term (at a low-dose) and Valium just once (at what I assume was a moderate-to-high dose) – it’s difficult to accurately compare the subjective effects of each medication. For a more accurate subjective assessment, I’d likely need to administer each medication at equal “relative” doses for the same duration following a washout phase with neurophysiologic recalibration between treatments (not something I’m interested in doing).
Which medication do you prefer: Valium or Xanax?
If you have personal experience with Valium (Diazepam) and Xanax (Alprazolam), share a comment mentioning whether you prefer one medication over the other. Assuming you prefer one medication over the other, mention some reason(s) as to why you’ve developed this preference.
Possible reasons might include: superior subjective efficacy; favorable tolerability (e.g. fewer side effects); lower cost; less severe discontinuation symptoms. In the event that you perceive one medication as being more effective than the other (e.g. Valium over Xanax), have you considered that the relative dosage might’ve been greater for one medication (thus exerting a stronger neurophysiologic effect)?
Have you also considered that gene expression influencing hepatic metabolism (CYP450 enzymes) might explain why Valium works better than Xanax (or vice-versa)? Have you noticed any differences in side effects or withdrawal symptoms between Valium and Xanax?
To help others better understand your experience with each medication, provide details such as: the duration over which you used each medication; the dosages and formats of each; the medical condition for which each medication was prescribed to treat (e.g. generalized anxiety disorder); and whether you used other substances along with Valium and/or Xanax.