Benzodiazepines (BZDs) are one of the most commonly taken psychotropic drugs, often used for anxiety. Prolonged use of BZDs is a widespread phenomenon in medical practice yet it may surprise you to know that these medications are really only meant to be used short-term. Both alprazolam (Xanax) and lorazepam (Ativan) are considered short-acting BZDs and when used for the right reasons are quite effective.
Many of you wonder: are they the same? Which is better? What is the difference between the two?
What are they used for?
Alprazolam (Xanax) is used for the treatment of anxiety disorder; short-term relief of symptoms of anxiety; panic disorder, with or without agoraphobia; and anxiety associated with depression. Lorazepam (Ativan) is approved for management of anxiety disorders, short-term (≤ 4 months) relief of anxiety symptoms, anxiety associated with depressive symptoms, or anxiety/stress-associated insomnia. Important distinction here is Xanax has approval for use in panic disorder, Ativan does not.
Which one is better for anxiety?
Numerous randomized trials have found both alprazolam (in standard and extended release formulations) and lorazepam work well for panic disorder. The onset of the anti-panic effects of benzodiazepines is very rapid, beginning within the first week of treatment which is why they are popular. Longer term anxiety meds, like selective serotonin reuptake inhibitors or SSRIs, take a few weeks to work so this may be a distinct advantage in severely symptomatic and impaired patients who require rapid relief.
However, only alprazolam and clonazepam (Klonopin) are approved by the FDA for the treatment of panic disorder, not lorazepam. The reason alprazolam and lorazepam carry the stigma of higher potential for abuse compared to a longer acting BZD like clonazepam (Klonopin) is that their short half-life and rapid onset of action requires more pill taking (3 – 4 times a day) and may reinforce pill-taking to alleviate anxiety, thus enhancing the potential for abuse.
What are the dosages?
Some differences here. Xanax is the brand name for alprazolam. Unlike lorazepam, alprazolam comes in an immediate and an extended release form (XR). The usual dose of immediate release alprazolam is 0.25 mg – 0.5 mg every 8 hours as needed. The extended release alprazolam or Xanax XR is 0.5 mg – 1 mg twice a day. Lorazepam is also used for anxiety disorder as well as insomnia due to anxiety or stress. Lorazepam 1 mg – 2 mg is used daily in 2 – 3 divided doses, and for insomnia 2 mg – 4 mg at bedtime.
The same warnings apply for both here. Reduce your dose, don’t stop abruptly if you’ve been taking it for more than 2 weeks. Abrupt discontinuation should be avoided—instead lower your daily dose by 0.5 mg every 3 days.
Pretty much the same. Most are from nervous system depression, which causes cognitive dysfunction, depression, dizziness, drowsiness, dysarthria (a motor speech disorder), fatigue, irritability, memory impairment, and sedation.
How fast do they work and how long do they last?
There are some subtle differences between the two here. This is important if you are using them before getting on a plane, having a root canal, or getting into an MRI scanner.
With alprazolam (Xanax) the onset of action for BOTH the immediate release and extended release formulations is 1 hour. Regular alprazolam will work for about 5 hours; extended release about 11 hours. Lorazepam has a more rapid onset of action, 30 – 60 minutes, and may last up to 8 hours. Both are cleared by the liver, so they will last longer in folks with liver disease. Interesting fact is that alprazolam lasts longer in Asians (25% longer half life compared to Caucasians), obese patients, and the elderly.
What about cost?
Xanax and Ativan tablets are both scored, so pill splitting is an option. Xanax comes in 0.25 to 2 mg tablets as does the generic alprazolam. The extended release Xanax or the generic alprazolam XR comes in 0.5 mg to 3 mg doses. The extended release tablets should never be broken or split. Your generic will always be cheaper than your brand name, immediate or extended release. Ativan is available as a brand name or generic (lorazepam) in 0.5 mg, 1 mg and 2mg tablets. The generic lorazepam is quite cheap.
The big downside:
Psychological dependence. Long term use of both alprazolam and lorazepam carries the same risk of the development of physical and psychological dependence and withdrawal symptoms when discontinuing them. Studies show that when either lorazepam or alprazolam are used for more than one month, dependence will occur in 47% of those taking them. That’s high, right?
Both shouldn’t really be used long term and treatment for more than 4 months should be re-evaluated to determine the patient’s continued need for the drug. Really, short-term.