Benzodiazepine withdrawal syndrome (BZD withdrawal) is the cluster of signs and symptoms that may emerge when a person who has been taking benzodiazepines develops a physical dependence on them and then reduces the dose or stops taking them without a safe taper schedule.

Typically, benzodiazepine withdrawal is characterized by sleep disturbance, irritability, increased tension and anxiety, depression, panic attacks, hand tremor, shaking, sweating, difficulty with concentration, confusion and cognitive difficulty, memory problems, dry mouth, nausea and vomiting, diarrhea, loss of appetite and weight loss, burning sensations and pain in the upper spine, palpitations, headache, nightmares, tinnitus, muscular pain and stiffness, depersonalization, restless legs syndrome, seizures, suicidal ideation, and a host of perceptual changes.

Benzodiazepine withdrawal can also lead to disturbances in mental function that persist for several months or years after onset of symptoms (referred to as post-acute-withdrawal syndrome in this form).

Withdrawal symptoms can be managed by educating patients about the nature and expected course of benzodiazepine withdrawal, individualized taper strategies according to withdrawal severity, the addition of alternative strategies such as reassurance, and referral to benzodiazepine withdrawal support groups.

Signs and symptoms Withdrawal symptoms occur during dose reduction and may include insomnia, anxiety, distress, weight loss, dizziness, night sweats, shaking, muscle twitches, aphasia, panic attacks, depression, numbness, dissociation, paranoia, indigestion, diarrhea, and photophobia. As withdrawal progresses, patients often find their physical and mental health improves with improved mood and improved cognition.

A more complete list of possible symptoms stated in publications:

Rapid discontinuation may result in a more serious syndrome

Mechanism

The neuroadaptive processes involved in tolerance, dependence, and withdrawal mechanisms implicate both the GABAergic and the glutamatergic systems. Gamma-Aminobutyric acid (GABA) is the major inhibitory neurotransmitter of the central nervous system; roughly one-quarter to one-third of synapses use GABA. GABA mediates the influx of chloride ions through ligand-gated chloride channels called GABAA receptors. When chloride enters the nerve cell, the cell membrane potential hyperpolarizes thereby inhibiting depolarization, or reduction in the firing rate of the post-synaptic nerve cell. Benzodiazepines potentiate the action of GABA, by binding a site between the α and γ subunits of the 5-subunit receptor thereby increasing the frequency of the GABA-gated chloride channel opening in the presence of GABA.

When potentiation is sustained by long-term use, neuroadaptations occur which result in decreased GABAergic response. What is certain is that surface GABAA receptor protein levels are altered in response to benzodiazepine exposure, as is receptor turnover rate. The exact reason for the reduced responsiveness has not been elucidated but down-regulation of the number of receptors has only been observed at some receptor locations including in the pars reticulata of the substantia nigra; down-regulation of the number of receptors or internalization does not appear to be the main mechanism at other locations. Evidence exists for other hypotheses including changes in the receptor conformation, changes in turnover, recycling, or production rates, degree of phosphorylation and receptor gene expression, subunit composition, decreased coupling mechanisms between the GABA and benzodiazepine site, decrease in GABA production, and compensatory increased glutamatergic activity. A unified model hypothesis involves a combination of internalization of the receptor, followed by preferential degradation of certain receptor sub-units, which provides the nuclear activation for changes in receptor gene transcription.

It has been postulated that when benzodiazepines are cleared from the brain, these neuroadaptations are "unmasked", leading to unopposed excitability of the neuron. Glutamate is the most abundant excitatory neurotransmitter in the vertebrate nervous system. Increased glutamate excitatory activity during withdrawal may lead to sensitization or kindling of the CNS, possibly leading to worsening cognition and symptomatology and making each subsequent withdrawal period worse. Those who have a prior history of withdrawing from benzodiazepines are found to be less likely to succeed the next time around.

Diagnosis In severe cases, the withdrawal reaction or protracted withdrawal may exacerbate or resemble serious psychiatric and medical conditions, such as mania, schizophrenia, agitated depression, panic disorder, generalised anxiety disorder, and complex partial seizures and, especially at high doses, seizure disorders. Failure to recognize discontinuation symptoms can lead to false evidence for the need to take benzodiazepines, which in turn leads to withdrawal failure and reinstatement of benzodiazepines, often to higher doses. Pre-existing disorder or other causes typically do not improve, whereas symptoms of protracted withdrawal gradually improve over the ensuing months.

Symptoms may lack a psychological cause and can fluctuate in intensity with periods of good and bad days until eventual recovery.

Prevention According to the British National Formulary, it is better to withdraw too slowly rather than too quickly from benzodiazepines. The rate of dosage reduction is best carried out so as to minimize the symptoms' intensity and severity. Anecdotally, a slow rate of reduction may reduce the risk of developing a severe protracted syndrome.

Long half-life benzodiazepines like diazepam or chlordiazepoxide are preferred to minimize rebound effects and are available in low dose forms. Some people may not fully stabilize between dose reductions, even when the rate of reduction is slowed. Such people sometimes simply need to persist as they may not feel better until they have been fully withdrawn from them for a period of time.

Management

Management of benzodiazepine dependence involves considering the person's age, comorbidity and the pharmacological pathways of benzodiazepines. Psychological interventions may provide a small but significant additional benefit over gradual dose reduction alone at post-cessation and at follow-up. The psychological interventions studied were relaxation training, cognitive-behavioral treatment of insomnia, and self-monitoring of consumption and symptoms, goal-setting, management of withdrawal and coping with anxiety.

There is no standard approach to managing benzodiazepine withdrawal. With sufficient motivation and the proper approach, almost anyone can successfully withdraw from benzodiazepines. However, a prolonged and severe withdrawal syndrome can cause profound disability, which may lead to breakdown of relationships, loss of employment, financial difficulties, as well as more serious adverse effects such as hospitalization and suicide. As such, long-term users should not be forced to discontinue against their will.

Over-rapid withdrawal, lack of explanation, and failure to reassure individuals that they are experiencing temporary withdrawal symptoms led some people to experience increased panic and fears they are going mad, with some people developing a condition similar to post-traumatic stress disorder as a result. A slow withdrawal regimen, coupled with reassurance from family, friends, and peers improves the outcome. According to a 2015 Cochrane review, cognitive behavior therapy plus taper was effective in achieving discontinuation in the short-term but the effect was not certain after six months.

Medications While some substitutive pharmacotherapies may have promise, current evidence is insufficient to support their use. Some studies found that the abrupt substitution of substitutive pharmacotherapy was actually less effective than gradual dose reduction alone, and only three studies found benefits of adding melatonin, paroxetine, trazodone, or valproate in conjunction with a gradual dose reduction.

Antipsychotics are generally ineffective for benzodiazepine withdrawal-related psychosis. Antipsychotics should be avoided during benzodiazepine withdrawal as they tend to aggravate withdrawal symptoms, including convulsions. Some antipsychotic agents may be riskier than others during withdrawal, especially clozapine, olanzapine or low potency phenothiazines (e.g., chlorpromazine), as they lower the seizure threshold and can worsen withdrawal effects; if used, extreme caution is required. Barbiturates are cross tolerant to benzodiazepines and should generally be avoided; however phenobarbital can be used, as it is relatively safe, see below. Benzodiazepines or cross tolerant drugs should be avoided after discontinuation, even occasionally. These include the nonbenzodiazepines Z-drugs, which have a similar mechanism of action. This is because tolerance to benzodiazepines has been demonstrated to be still present at four months to two years after withdrawal depending on personal biochemistry. Re-exposures to benzodiazepines typically resulted in a reactivation of the tolerance and benzodiazepine withdrawal syndrome. Bupropion, which is used primarily as an antidepressant and smoking cessation aid, is contraindicated in people experiencing abrupt withdrawal from benzodiazepines or other sedative-hypnotics (e.g. alcohol), due to an increased risk of seizures. Buspirone augmentation was not found to increase the discontinuation success rate. Caffeine may worsen withdrawal symptoms because of its stimulatory properties. At least one animal study has shown some modulation of the benzodiazepine site by caffeine, which produces a lowering of seizure threshold. Carbamazepine, an anticonvulsant, appears to have some beneficial effects in the treatment and management of benzodiazepine withdrawal; however, research is limited and thus the ability of experts to make recommendations on its use for benzodiazepine withdrawal is not possible at present. Ethanol, the primary alcohol in alcoholic beverages, even mild to moderate use, has been found to be a significant predictor of withdrawal failure, probably because of its cross tolerance with benzodiazepines. Flumazenil has been found to stimulate the reversal of tolerance and the normalization of receptor function. However, further research is needed in the form of randomised trials to demonstrate its role in the treatment of benzodiazepine withdrawal. Flumazenil stimulates the up-regulation and reverses the uncoupling of benzodiazepine receptors to the GABAA receptor, thereby reversing tolerance and reducing withdrawal symptoms and relapse rates. Because of limited research and experience compared to the possible risks involved, the flumazenil detoxification method is controversial and can only be done as an inpatient procedure under medical supervision.

Flumazenil was found to be more effective than placebo in reducing feelings of hostility and aggression in patients who had been free of benzodiazepines for 4–266 weeks. This may suggest a role for flumazenil in treating protracted benzodiazepine withdrawal symptoms.