Prescription drugs used to treat anxiety
There are several different groups of prescribed drugs that can be used.
Benzodiazepines are effective anxiolytic's (calming medications). These medications are often prescribed by doctors to almost any individual who has stress related symptoms, minor physical disease or even simply unhappiness. According to medical authorities they are often prescribed in situations which are not justified. In particular they are inappropriate drugs for treating depression or chronic psychosis. In situations of bereavement, medical studies have shown that the normal psychological adjustment to bereavement and loss may be prevented or inhibited by benzodiazepines. They should only rarely be prescribed the children in situations caused by fear for example before surgery or in instances of severe acute anxiety and related insomnia.
It is sensible to keep the prescribed dose to the lowest possible dose for the shortest length of time. The main problem with benzodiazepines is the development of dependence and the problem of withdrawal symptoms, when benzodiazepines are stopped. Addiction and dependence to benzodiazepines is especially likely to happen in individuals who have a history of alcohol or drug abuse. Dependence is also more common in patients with marked personality disorders.
Benzodiazepine anxiolytic's are sometimes referred to as minor tranquillisers in contrast to antipsychotic drugs such as chlorpromazine which are referred to as major tranquillisers. However this term minor tranquillisers is misleading because not only do they differ significantly from major tranquillisers but they use is by no means minor.
Doctors are advised that benzodiazepines are only indicated for the short-term relief of "severe anxiety". Doctors are taught and advised that the long-term use of benzodiazepines should be avoided. This is the advice given by the committee on safety of medicines (CSM) in the United Kingdom.
The duration of action of benzodiazepines varies. For example diazepam, alprazolam, chlordiazepoxide and clobazam have a prolonged duration of action. Shorter acting benzodiazepines include lorazepam and oxazepam.
For the treatment of panic disorder which is resistant to antidepressants therapy then a benzodiazepine such as lorazepam or clonazepam may be helpful. Sometimes, in fact quite often, when patients are started on antidepressants, particularly selective serotonin reuptake inhibitors (SSRI's) such as fluoxetine or citalopram, these patients experience a worsening of anxiety symptoms. In this situation the use of a short course of benzodiazepines is very helpful relieving the symptoms of nervousness. Doctors occasionally treat patients with severe panic attacks with an an intravenous injection of diazepam or lorazepam.
Diazepam has a number of medical indications. These include short-term us in anxiety or insomnia. Diazepam is also useful to treat acute alcohol withdrawal, status epilepticus, febrile convulsions (fits), and muscle spasms. It is also used to treat fear and apprehension before surgery.
Side effects of diazepam include: drowsiness, sleepiness and light-headedness. Other side-effects include confusion and unsteadiness (ataxia), especially in the elderly. Diazepam side-effects also include amnesia, dependence, a paradoxical increase in aggression, muscle weakness and less frequently headache, vertigo, low blood pressure, visual disturbances and dysarthria.
The usual dose of of diazepam taken by mouth is 2 mg three times a day. This dose may be increased up to a total dose of 15 or 30 mg daily in divided doses. It is recommended that elderly patients are prescribed half the adult dose. As a treatment for insomnia the dose of diazepam is 5 to 15 mg taken at night.
Diazepam in United Kingdom comes in three strengths by mouth: 2 mg, 5 mg and 10 mg tablets.
The medical indications of alprazolam are the same as those with diazepam. Alprazolam has similar side-effects to diazepam.
The dose of alprazolam is 250 to 500 µg three times daily. This dose may be increased to a total of 3 mg daily in divided doses. In the elderly the recommended dose is 250µg 2 to 3 times daily. The usage of alprazolam is not recommended in children.
In the United Kingdom alprazolam is manufactured in strengths of 250 µg and 500 µg tablets.
Chlordiazepoxide (Librium, Tropium)
Chlordiazepoxide has similar indications to diazepam. Chlordiazepoxide is often used to treat acute alcohol withdrawal. The side-effects of chlordiazepoxide are similar to those of diazepam.
The dose of chlordiazepoxide which is 10 mg three times a day. This dose can be increased to 60 to 100 mg daily in divided doses. In the elderly half the adult dose should be used. Chlordiazepoxide is not recommended in children.
In the United Kingdom chlordiazepoxide is manufactured in strengths of 5 mg and 10 mg capsules or tablets.
Lorazepam is indicated for the short-term treatment of anxiety or insomnia. Lorazepam is also indicated for the treatment of status epilepticus and is used by anaesthetists before surgery as a pre-med. The side-effects of lorazepam are similar to those of diazepam.
The dose of lorazepam used is 1 to 4 mg daily in divided doses. In the elderly half the adult dose is used. For the treatment of insomnia the dose is 1 to 2 mg at night. Lorazepam is not recommended in children.
In the United Kingdom lorazepam is manufactured in 1 mg and 2.5 mg tablets.
Oxazepam is indicated for the short-term treatment of anxiety. The side-effects of oxazepam are similar to those of diazepam.
The dose of oxazepam is 15 to 30 mg 3 to 4 times daily. In the elderly the recommended dose of oxazepam is 10 to 20 mg three to four times daily. Oxazepam should not be used in children.
In the United Kingdom oxazepam is manufactured in 10 and 15 mg tablets.
Azapirones are another class of drugs that are used to treat anxiety. They are chemically unrelated to benzodiazepines. Examples include buspirone (Buspar), and tandospirone.
Buspirone is currently the only azapirone used as an anxiolytic in the Western world. Tandospirone (Sediel) is used in China and Japan as an anxiolytic. There are other azapirones which are being developed by pharmaceutical companies for the treatment of anxiety.
Buspirone is thought to work by action at specific serotonin receptors. It is thought to act on the 5HT1A receptors. Buspirone is slow to work as an anxiolytic and the response to treatment may take up to 2 weeks. Buspirone does not relieve the symptoms of benzodiazepine withdrawal. If a patient is taking a benzodiazepine it is important to still reduce the dose of the benzodiazepine gradually and it is sensible and advisable to do this before starting buspirone.
The potential of buspirone to cause dependence and to be abused is low. However buspirone is still only advised and licensed for short-term use. However psychiatrists and specialists do occasionally treat anxiety in patients with buspirone for several months. Indications for buspirone Buspirone is indicated for the treatment of anxiety and is only licensed for short-term use.
Side effects of buspirone These include nausea, dizziness, headache, nervousness and excitement. Rare side-effects of buspirone include dry mouth, tachycardia, palpitations, chest pain, drowsiness, confusion, seizures, fatigue, tiredness and sweating.
Dose of buspirone The dose of buspirone is 5 mg two to three times a day, increased as necessary every two to three days. The usual dose range is 15 to 30 mg daily. The maximum daily dosage is 45 mg.
In the United Kingdom buspirone is manufactured in 5 mg and 10 mg tablets.
Meprobamate (Equanil, Miltown, Meprospan).
Meprobamate is an older medication which was used to treat "nerves". Meprobamate is a carbamate derivative and is chemically unrelated to benzodiazepines and azapirones. Meprobamate was first available in 1955. It was very widely used to treat "nerves" but it it has now been widely replaced by benzodiazepines.
Indications for meprobamate Meprobamate is indicated for the short-term treatment of anxiety. It has been found to be less effective than the benzodiazepines for this purpose. Meprobamate is also more dangerous in overdosage than benzodiazepines. Meprobamate has potential to cause dependence and addiction.
The European medicines agency recommended suspension throughout the European Union of all medications containing meprobamate on January 19, 2012. This was because of serious side-effects seen with the medicine.
Side-effects of meprobamate These include drowsiness, confusion, unsteadiness, amnesia, dependence, gastrointestinal disturbances, low blood pressure, paraesthesia, weakness, headache, paradoxical excitement, visual disturbance and rarely agranulocytosis and rashes. The side-effects of meprobamate tend to be more frequent and severe than those with diazepam. The dose of meprobamate is 400 mg 3 to 4 times daily. Elderly patients should take half the adult dose. Meprobamate is not recommended in children.
The committee on safety of medicines (CSM) in the UK advise that meprobamate treatment should not be initiated in new patients. Meprobamate is manufactured in 400 mg tablets.
Barbiturates work by depressing the central nervous system. They have a wide variety of effects from mild sedation to total anaesthesia. They are effective as hypnotics, anxiolytics and anticonvulsants. Barbiturates are highly addictive both physically and psychologically.
They have now largely been replaced by benzodiazepines as a treatment for "nerves". This is because benzodiazepines are significantly less dangerous in overdose than barbiturates. These days barbiturates only have a place in the treatment of severe intractable insomnia in individuals who are already taking barbiturates.
The committee on safety of medicines in the UK advises that barbiturates should be avoided in the elderly. The long acting barbiturate phenobarbitone is still sometimes of value in the treatment of epilepsy but its use for treating "nerves" and as a sedative is not justified. The very short acting barbiturate thiopental is used in anaesthesia. Indications for barbiturates. The UK committee on safety of medicines advises that barbiturates are indicated for the treatment of severe intractable insomnia only in patients who are already taking barbiturates.
Examples of barbiturates.
Examples of barbiturates include Sodium Amytal (amyolbarbitone, amobarbital), Soneryl (butobarbitone, butobarbital), Seconal Sodium (secobarbital, quinalbarbitone), and Tuinal (a mixture of amobarbital 50mg and secobarbital 50mg. Other barbiturates include pentobarbital (Nembutal) and phenobarbital (Luminal). Mode of Action of barbiturates.
The main mechanism of action of barbiturates work is thought to be that they bind to the GABA a receptors at the alpha subunit.
Side-effects of barbiturates. Adverse effects of barbiturates include drowsiness and incoordination. Less frequent side-effects include nausea, vomiting, constipation, liver damage, bradycardia, hypotension, syncope, hypoventilation, apnoea, respiratory depression, agitation, confusion, hyperkinesia, ataxia (impaired coordination), CNS depression, sleep disorders, hallucinations, anxiety, dizziness, headache, paradoxical excitement, impaired memory (amnesia), fever and megaloblastic anaemia.
Barbiturates available in the UK.
Sodium Amytal is manufactured in the UK in 60 mg capsules Soneryl is manufactured in the UK in 100 mg tablets Seconal Sodium is manufactured in the UK in 100 mg capsules Tuinal is manufactured in the UK in capsules containing amobarbital sodium 50 mg and secobarbital sodium 50 mg.
Selective serotonin reuptake inhibitors (SSRI's)
The selective serotonin reuptake inhibitors are a group of drugs that were initially developed and are mainly prescribed as antidepressants. It has been discovered that they are effective treatments for anxiety.
Examples of selective serotonin reuptake inhibitors include fluoxetine (Prozac), fluvoxamine (Faverin), paroxetine (Seroxat), citalopram (Cipramil) and escitalopram (Cipralex).
Selective serotonin reuptake inhibitors work by blocking the uptake of serotonin into nerve endings in the brain. In effect they are increasing amount of serotonin present. Serotonin is known to be a calming and mood elevating chemical. Increased levels of serotonin have a calming and anti-depressant effect. Selective serotonin reuptake inhibitors make better use of available serotonin which is already present in the brain.
SSRI's are not calming drugs in their own right, unlike benzodiazepines which are directly calming chemicals. This makes SSRI's very different from benzodiazepines, meprobamate and barbiturates.
SSRI's take longer to work in calming nervousness and relieve depression, because the level of serotonin in the brain builds up slowly. This is unlike tranquilisers such as benzodiazepines, which work quickly. When taken by mouth benzodiazepines can treat anxiety in as little as 30 minutes to one hour. When diazepam is given intravenously, by injection, it can work in a matter of seconds or a few minutes. In contrast SSRI's can take several weeks to work as an anxiolytic or relieve depression.
SSRI's have also been shown to have an effect, in parts of the brain, known as neurogenesis. SSRI's such as fluoxetine have been found to cause new nerve cells to grow in certain parts of the brain. In particular SSRI's result in new nerves growing in the hippocampus. The hippocampus is a part of the brain which is important for processing short-term memories.
Another benefit of SSRI's is that they are not thought to be addictive. SSRI's such as fluoxetine, paroxetine and citalopram can be taken long term for the treatment of anxiety and social phobia.
Serotonin-norepinephrine reuptake inhibitors (SNRI's). These are also known as dual reuptake inhibitors. Known as serotonin-norepinephrine reuptake inhibitors in the US and as serotonin-noradrenaline reuptake inhibitors in the UK. Examples of SNRI's include venlafaxine (Effexor, Efexor), desvenlafaxine (Pristiq) and duloxetine (Cymbalta, Yentreve). These drugs work on both serotonin and noradrenaline.
Beta-blockers such as propranolol (Inderal, Innopran XL, Avlocardyl, Deralin, Bedranol SR), atenolol (Tenormin), bisoprolol (Concor, Concore, Zebeta, Monocor) and metoprolol (Lopressor, Toprol XL, Betaloc, Lopresor).