Benzodiazepines negative effects

Drugs that increase sedation and give muscle relaxation can have a negative effect on muscle strength and the ability to maintain physical activity, for example, benzodiazepines and other tranquilizers. Corticosteroids have a well known side effect on muscle tissue that leads to muscle atrophy and increases with the dosage. 

The generally excellent tolerability of these preparations has contributed greatly to the widespread use of anxiolytics. The commonest side effects (Table 1.11) are tiredness and muscle relaxation and these usually can be avoided or attenuated by reducing the dose. Ataxia and paradoxical reactions such as irritability and increased agitation occasionally arise in the elderly but are rare in younger patients. Much attention has been focused on the negative effects of benzodiazepines on memory and other cognitive functions (see Chapter 7). 

If excessive noradrenergic transmission is a causal factor in anxiety, then it would be predicted that a lesion of central noradrenergic neurons would have an anti-anxiety effect in behavioural models of this condition. Unfortunately, the behavioural effects of such lesions are notoriously inconsistent and there are many reports of negative findings (e.g. Salmon, Tsaltas and Gray 1989). One study has even shown that a lesion of central noradrenergic neurons, induced by the selective neurotoxin, DSP-4, abolishes the anti-anxiety effects of tricyclic antidepressants and MAO inhibitors, but not those of the benzodiazepine, alprazolam, or the barbiturate, phenobarbitone (Fontana,... 

We have already learned that benzodiazepines act on GABA receptors to amplify the effect of GABA and cause increased negative or inhibitory currents to enter the neuron and thus decrease the chance of that neuron firing an action potential. Because an action potential causes the release of neurotransmitter when it reaches the end of the neuron, the neurotransmitter that that particular neuron releases is reduced (Figure 4.2). In this section, we will look at the major neurotransmitter system that is affected when benzodiazepines are administered. 

People who have had previous negative reactions or serious side effects with any benzodiazepine. 

From alcohol and methamphetamine to Prozac, Valium, lithium, and Zyprexa, psychoactive substances disguise their adverse mental effects for the user. A person grossly mentally impaired by stimulants, benzodiazepine tranquilizers, mood stabilizers, or neuroleptics is likely to have little idea about how dysfunctional he or she has become. When the individual does perceive a change in himself or herself, positive or negative, it is almost never attributed to the causative agent the drug. If the individual feels euphoric, it is attributed to good fortune and especially... 

There arc also compounds that can occupy ben/txliazc-pine modulatory sites, have no effect on chloride flux them-.selves. and block positive and negative mixlulators. They have been called variously antagonists, zero inodulalors. and neutralizing allosteric nwdulators. One such compound, flu-mazenil. is used clinically to counteract the sedative effect of benzodiazepines. 

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