Ativan (lorazepam) and Xanax (alprazolam) are benzodiazepines (colloquially called benzos) used to treat anxiety disorders. Xanax is also prescribed for panic disorders. Both drugs work by enhancing the effect of the neurotransmitter GABA in the brain and are unsafe in pregnancy.
Studies have shown that both drugs demonstrate comparable efficacy and are prone to overdose and withdrawal symptoms. The difference lies in side effects, interaction with other drugs, and indications based on the medical history of the patient. While both drugs may have several side effects, Ativan — i.e., lorazepam — has at times known to have the exact opposite of its desired effect, especially on older people.
|Trade names||Xanax||Ativan and others|
|Prescribed for||Management of acute symptoms of anxiety disorders, panic disorders, anxiety caused by depression||Lorazepam is used to treat anxiety disorders|
|Pregnancy cat.||D (US) [Unsafe during pregnancy; see article for details]||D (US) [Unsafe during pregnancy; see article for details]|
|Dependence liability||High (addictive)||High|
|Half-life||Immediate release: 11.2 hours; Extended release: 10.7–15.8 hours||9–16 hours|
|Side effects||Drowsiness, dizziness, blurred vision, headache, memory problems, trouble concentrating, sleep problems, swelling in limbs, muscle weakness, lack of balance and coordination, slurred speech, upset stomach, nausea, vomiting, sweatiness, dry mouth etc.||Drowsiness, dizziness, irritability, loss of coordination, difficulty concentrating, dry mouth, increased salivation, changes in sex drive and appetite, nausea, constipation, weight changes, frequent urination.|
|Restrictions||Should not be used by people with narrow-angle glaucoma or who are taking Sporanix or Nizoral.||Allergies to benzodiazepines, such as alprazolam, clonazepam, diazepam. May have opposite effect on elderly.|
|Bioavailability||80–90%||85% of oral dose|
|Legal status||POM (UK) Schedule IV (US)||Schedule IV (CA) CD (Benz) POM (UK) Schedule IV (US)|
|Metabolism||Hepatic, via Cytochrome P450 3A4||Hepatic glucuronidation|
Ativan (generic name lorazepam) is a class of benzodiazepines used to treat anxiety disorders. Ativan comes as 0.5-milligram tablets, one-milligram tablets, two-milligram mg tablets and liquid. Lorazepam Intensol also goes under the brand Ativan.
Xanax (generic name alprazolam) is a class of benzodiazepines drugs used to treat anxiety and panic disorders. Xanax comes as 0.5-milligram tablets and extended-release tablets, one-milligram tablets and extended-release tablets, one-milligram caplets, two-milligram tablets and extended-release tablets, three-milligram tablets and extended-release tablets, orally-disintegrating tablets and liquid.
Directions for Use
Ativan is to be taken orally with or without food at the same time every day. The drug can take a few hours to several days to start working upon first starting.
Xanax should also be taken by mouth with or without food. Extended-release tablets should not be crushed or split as this releases all the medication at once. Xanax can also take a few hours to several days to start working upon first starting.
Ativan and Xanax should be stored at room temperature away from light and moisture. Ativan has a shelf life of two years, and Xanax has a shelf life of three years.
How it Works
Studies   comparing the efficacy of alprazolam and lorazepam conducted showed that both drugs demonstrated similar efficacy in reducing panic attacks and phobic behavior and a much higher efficacy compared to the placebo baseline.
Common side effects of Ativan include drowsiness, dizziness, loss of coordination, headache, nausea, blurred vision, change in sexual interest or ability, constipation, heartburn or change in appetite. Serious but rare side effects include mental or mood changes, such as hallucinations, depression or thoughts of suicide; slurred speech or difficulty talking; vision changes; unusual weakness; trouble walking; memory problems; signs of infection, such as fever or persistent sore throat; trouble breathing, especially during sleep; severe skin rash; yellowing of the skin or eyes; or an irregular heartbeat.
Common side effects of Xanax include drowsiness, light-headedness, headache, tiredness, dizziness, irritability, talkativeness, difficulty concentrating, dry mouth, increased salivation, changes in sex drive or ability, nausea, constipation, changes in appetite, weight changes, difficulty urinating or joint pain. Serious but rare side effects include shortness of breath, seizures, seeing things or hearing voices that do not exist, severe skin rash, yellowing of the skin or eyes, depression, memory problems, confusion, problems with speech, unusual changes in behavior or mood, thinking about harming or killing oneself or trying to do so or problems with coordination or balance.
Precautions and Contraindications based on Medical History
Patients are recommended to give a detailed medical history to their doctors before taking Ativan. They should especially mention kidney disease or liver disease, glaucoma, lung or breathing problems such as sleep apnea, mental or mood disorders such as depression and any drug or alcohol abuse. Ativan can cause allergic reactions in people who have allergies to other benzodiazepines, such as alprazolam, clonazepam or diazepam. Ativan can sometimes have the complete opposite of its intended effect on elderly people.
Patients should give a detailed medical history to their doctors before taking Xanax. Severe lung or breathing problems such as COPD and sleep apnea, liver disease, kidney disease, glaucoma and any drug or alcohol abuse should especially be mentioned. Xanax can cause allergic reactions in people who have allergies to other benzodiazepines, such as alprazolam, clonazepam or diazepam. Older adults may be more sensitive to the drug's side effects.
Patients should tell their doctors right away if they experience any of the following allergic reactions while taking Ativan: hives, difficulty breathing or swelling of the face, lips, tongue or throat.
Patients taking Xanax should inform their doctor right away if they experience any of the following allergic reactions: rash, itching or swelling, severe dizziness or trouble breathing.
People may experience withdrawal symptoms if they stop taking Ativan or Xanax suddenly. It is therefore recommended that dosage be reduced gradually (usually 0.5mg every three days).
Withdrawal symptoms for Xanax include seizures. Withdrawal symptoms include seizures, trouble sleeping, mental or mood changes, nausea, vomiting, diarrhea, loss of appetite, stomach pain, hallucinations, numbness or tingling of the arms and legs, muscle pain, fast heartbeat, short-term memory loss, very high fever and increased reactions to noise, touch or light. More on the withdrawal symptoms of Ativan in this video:
Overdose of Ativan may result in confusion, slow reflexes, clumsiness, deep sleep and loss of consciousness. Overdose of Xanax can cause drowsiness, confusion, problems with coordination and loss of consciousness.
Ativan can have negative effects when interacting with certain drugs: antihistamines; digoxin, or Lanoxin; levodopa, found in Larodopa and Sinemet; medications for depression, seizures, pain, Parkinson's disease, asthma, colds, or allergies; muscle relaxants; oral contraceptives; probenecid, or Benemid; rifampin, or Rifadin; sedatives; sleeping pills; theophylline, or Theo-Dur; tranquilizers; and valproic acid, or Depakene.
Xanax does not interact well with amiodarone, found in Cordarone and Pacerone; antidepressants, such as desipramine, imipramine, and nefazodone; antifungals such as fluconazole, posaconazole, or voriconazole; antihistamines; cimetidine, or Tagamet; clarithromycin, or Biaxin; cyclosporine, found in Neoral and Sandimmune; diltiazem, found in Cardizem, Dilacor and Tiazac; ergotamine, found in Cafatine, Cafergot and Wigraine; erythromycin, found in E.E.S., E-Mycin and Erythrocin; isoniazid, found in INH and Nydrazid; medications for mental illness, chronic pain, and seizures; nicardipine, or Cardene; nifedipine, found in Adalat and Procardia; oral contraceptives; propoxyphene, or Darvon; selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine, fluvoxamine, paroxetine, and sertraline; sedatives; sleeping pills; and tranquilizers.
- Wikipedia: Lorazepam
- Wikipedia: Alprazolam
- Benzodiazepine treatment of panic disorder - NIH.gov
- Ativan Oral Uses and How to Use - HealthCentral
- Lorazepam - NIH.gov
- Ativan - RxList
- Summary of Lorazepam Characteristics - Genus Pharma
- Alprazolam - NIH.gov
- Xanax Oral Uses and How to Use - HealthCentral
- Alprazolam - Medsafe
- Ativan (lorazepam) - National Alliance on Mental Illness
- The Effects of Lorazepam Use - Coalition Against Drug Abuse