Toxicity from propylene glycol has been reported in the case of a patient receiving a continuous lorazepam infusion.

What other drugs will affect Ativan?Before taking Ativan, tell your doctor if you are using any of the following drugs:* a barbiturate such as amobarbital (Amytal), butabarbital (Butisol), mephobarbital (Mebaral), secobarbital (Seconal), or phenobarbital (Luminal, Solfoton); * an MAO inhibitor such as isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam), or tranylcypromine (Parnate); * medicines to treat psychiatric disorders, such as chlorpromazine (Thorazine), haloperidol (Haldol), mesoridazine (Serentil), pimozide (Orap), or thioridazine (Mellaril); * narcotic medications such as butorphanol (Stadol), codeine, hydrocodone (Lortab, Vicodin), levorphanol (Levo-Dromoran), meperidine (Demerol), methadone (Dolophine, Methadose), morphine (Kadian, MS Contin, Oramorph), naloxone (Narcan), oxycodone (OxyContin), propoxyphene (Darvon, Darvocet); or * antidepressants such as amitriptyline (Elavil, Etrafon), amoxapine (Asendin), citalopram (Celexa), clomipramine (Anafranil), desipramine (Norpramin), doxepin (Sinequan), escitalopram (Lexapro), fluoxetine (Prozac, Sarafem), fluvoxamine (Luvox), imipramine (Janimine, Tofranil), nortriptyline (Pamelor), paroxetine (Paxil), protriptyline (Vivactil), sertraline (Zoloft), or trimipramine (Surmontil). edit PharmacologyLorazepam has anxiolytic, sedative, hypnotic, amnesic, anticonvulsant as well as muscle relaxant properties. Avoid using other medicines that make you sleepy. Lorazepam is more effective than diazepam in the treatment of status epilepticus. Partial, but incomplete tolerance develops to these impairments. nausea and vomiting caused or worsened by psychological sensitization to the thought of being sick. Do not start using a new medication without telling your doctor. Do not use this medication without telling your doctor if you are breast-feeding a baby. Benzodiazepines can cause or worsen depression. Of drugs used in attempted suicide, benzodiazepines are the most commonly used pharmaceutical drug, with 26% of attempted suicides involving benzodiazepines.