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Anxiety: Panic
 

Signs & Symptoms

An estimated 30% of all adults have experienced at least one panic attack, with women being twice as likely as men to have panic disorder. Attacks occur suddenly out of the blue, and start with a sense of foreboding, accompanied by physical symptoms such as shortness of breath, rapid heartbeat, chest pain and flushing in the face. Usually, the attack comes on within 10 minutes of feeling something isn¹t right, builds to a peak and then subsides in under 30 minutes. For many, the attack may happen only a few times in a whole lifetime but for others, panic attacks can occur many times a week.

Panic attacks are typically brief and self-contained but they can be severely debilitating if left untreated. Take for example, Lenny J. The first time Lenny¹s symptoms occurred, he was flying to Montreal on a routine business trip. Nothing in particular happened, but suddenly within about 10 minutes from takeoff, he was overwhelmed with a feeling that something disastrous was going to happen. His heart started racing, each beat a painful thump inside his chest, and his fingers felt all numb and tingling.

He also felt as if he couldn¹t breathe ­ in fact, Lenny was convinced he was dying. Over the next 15 or 20 minutes, the attack subsided and Lenny made it to Montreal ­ and back. But the experience was so intensely awful, and the anticipation that it might happen again so unnerving, that Lenny eventually stopped flying. That same scenario can happen anywhere ­ in a mall, in a car, while waiting for a doctor¹s appointment, at work, at home.


... hope is brightest when it dawns from fears.

Sir Walter Scott 1771-1832

Not knowing when the next attack is going to occur, people also tend to develop anticipatory anxiety which often sets the stage for another panic attack. Thus, the anxiety becomes a vicious cycle, and people understandably start to avoid the mall, the car, the doctor, work ­ in fact, they begin to be afraid of going anywhere.

When panic disorder develops into a fear of a situation or a place where escape might be difficult or embarrassing, the disorder is also called ³agoraphobia².
 
Treatment

Panic disorder responds best to a combination of cognitive behavioural therapy (CBT) and antidepressant medication. CBT helps people learn to deal with the intense anxiety and feel more in control, while the antidepressants can block the panic attacks from occurring. Although relative newcomers in the field of panic disorder, the SSRIs are now considered the treatment of choice for panic and other types of anxiety disorders.

As their name suggests, the SSRIs affect only serotonin in the brain, which explains why they are called "selective".

There are many different cells in the brain which serotonin affects and each of these cells regulates a different function - mood, sleep, appetite and sexuality among them.

SSRIs amplify serotonin's effects by slowing its removal from the synapse between brain cells. With more serotonin to transmit, the function between brain cells is slowly restored to normal and with this balance comes resolution of the anxiety disorder. Used in the treatment of panic and other types of anxiety disorders, the SSRIs produce both anxiolytic or anti-anxiety as well as antidepressant effects.

They are also much safer than either the tricyclic antidepressants (TCAs) or the monoamine oxidase inhibitors (MAOIs) - both, incidentally, still useful in patients with panic disorder, especially if they also have co-existing depression. Because the SSRIs do not affect the cholinergic system, they have none of the anticholinergic effects associated with TCAs, including dry mouth, blurred vision, constipation, problems with urination, and difficulties with memory and concentration.

The TCAs and the MAOIs may also worsen symptoms of anxiety in up to one-third of patients at the start, and if either of these two classes of agents are used, they are usually given along with one of the benzodiazepines, which have a more immediate effect on anxiety. The SSRIs, in turn, act as a sort of "behavioral brake" in the brain, and drugs which boost serotonin's activity like the SSRIs tend to dampen a wide range of impulses including sexual response. Increasingly recognized as a side effect of all SSRIs, it's now felt that over 60% of people on an SSRI may experience decreased sexual desire, difficulties with orgasm or erection and other sexual problems.

In anxiety disorders, the tendency of some of the SSRIs to cause agitation, restlessness and insomnia may also be heightened, which is why doctors start with a low dose at the beginning of therapy. An additional use of a benzodiazepine may be required for two to four weeks until the anti-anxiety effects from the SSRI take hold as well.

Two of the newer cyclic antidepressants, Serzone (nefazodone) and Effexor (venlafaxine) may also be effective in panic disorder, although experience with these agents is limited.

Similarly, an anxiolytic known as Buspar (buspirone) has not been found effective in panic disorder, although it may be useful in the treatment of other anxiety states.

Following treatment, about one-third of people with panic disorder do very well, about one-half are improved with some remaining symptoms and about 20 to 30% remain symptomatic.

In Canada, currently recommended SSRIs for the treatment for panic disorder include: fluoxetine (Prozac), fluvoxamine (Luvox), paroxetine (Paxil), and sertraline (Zoloft). Venlafaxine (Effexor) and nefazodone (Serzone) may also be used.

How to minimize side effects when taking an SSRI

Benzodiazepines

The benzodiazepines are most often used together with an SSRI to provide symptomatic relief for the first few weeks before the effects of the SSRI kick in. The benzodiazepines probably have an unfair reputation of being so addictive that people can never go off them. ("I'm Dancing as Fast as I Can" was one such story popularizing that notion). In point of fact, many people respond well to a benzodiazepine, they don't develop tolerance to the drug's effects and they don't get "hooked".

Especially for panic disorder, agoraphobia and social phobias, two benzodiazepines most often used to treat symptoms are Xanax (alprazolam) and Rivotril/Klonopin (clonazepam); Ativan (lorazepam) can also be used. These agents differ in the length of duration of action and this means that people taking Xanax for example, will need to take their medications more often during the day than people taking Rivotril or Klonopin. Other than that, the medications are essentially similar in their "dampening down" effect on the brain which helps quell symptoms of anxiety. Side effects with the benzodiazepine are actually not that marked and they often disappear when the dose of the medication is adjusted.

The most common of these effects are of a generalized sedative nature: fatigue, drowsiness, confusion, decreased concentration, headache, dizziness, muscle weakness and poor coordination. Confusion and disorientation, primarily in the elderly, have been reported, as have sexual dysfunction in some people. However, the most worrisome effect associated with benzodiazepine use, especially longer-term use, is the development of so-called "tolerance" to the drug's effects.

After about four months of continuous treatment, the effect of the drug can be lost and the dose may have to be increased to regain symptom control. As well, when treatment is stopped, especially abruptly, withdrawal symptoms can be quite intense and anxiety may worsen considerably. This is why doctors "taper" off the dose when prescribing any benzodiazepine, sometimes over a period of months, to minimize withdrawal symptoms.

In Canada, benzodiazepines recommended for the treatment and prevention of panic disorder include: alprazolam (Xanax) and clonazepam (Rivotril or Klonopin).

How to minimize side effects when taking a benzodiazepine






Panic disorder is best treated with a combination of cognitive behavioural therapy (CBT), which helps people learn to deal with the intense anxiety and feel more in control, and antidepressant medication to block the panic attacks from occurring.