The EP 904 white pill is a prescription medication containing Lorazepam 0.5 mg. Manufactured by Excellium Pharmaceutical (and formerly by Leading Pharma), it is a generic form of the brand-name medication Ativan.
Lorazepam belongs to the class of drugs known as benzodiazepines and is classified as a Schedule IV controlled substance in the United States due to its potential for dependence, abuse, and misuse.
Physical Identification
Characteristic Details
- Active Ingredient Lorazepam (0.5 mg)
- Imprint “EP 904” on one side, plain on the other side
- Shape Round, flat face, beveled edge
- Color White
- Score Line Unscored (0.5 mg strength)
- Primary Manufacturer/Packager Excellium Pharmaceutical Inc.
- Verification Tip: Higher dosage strengths from the same manufacturer carry different imprints: the 1 mg tablet is debossed with EP 905 (scored) and the 2 mg tablet is debossed with EP 906 (scored).
Mechanism of Action
Lorazepam works by enhancing the effects of a naturally occurring inhibitory neurotransmitter in the central nervous system (CNS) called gamma-aminobutyric acid (GABA).
- GABA-A Receptor Binding: Lorazepam binds specifically to the benzodiazepine site on the GABA-A receptor complex in the brain.
- Enhanced Chloride Influx: This binding increases the frequency with which the chloride ion channel opens, allowing more chloride ions to enter the neuron.
- Hyperpolarization & CNS Depression: The influx of negatively charged chloride hyperpolarizes the neuronal membrane, making it less likely to fire. This produces widespread anxiolytic (anti-anxiety), sedative, anticonvulsant, and muscle-relaxant effects.
Indications & Dosing
Lorazepam is primarily indicated for the short-term relief of anxiety disorders or anxiety associated with depressive symptoms. It is generally intended for short-term use (e.g., 2 to 4 weeks) as long-term safety and efficacy beyond 4 months have not been well-established.
Standard Adult Dosage (Oral)
- Anxiety Disorders: The usual starting dose is 2 mg to 3 mg per day, given orally in 2 or 3 divided doses (e.g., 1 mg two to three times daily or 0.5 mg multiple times daily). Daily doses typically range from 1 mg to 10 mg per day depending on severity.
- Insomnia due to Anxiety: A single daily dose of 1 mg to 2 mg taken at bedtime.
Special Dosage Considerations
- Elderly or Debilitated Patients: The recommended starting dose is 1 mg to 2 mg per day in divided doses, adjusted as needed, to reduce the risk of excessive sedation or ataxia (loss of coordination).
- Renal or Hepatic Impairment: Doses should be carefully titrated due to decreased clearance and potential accumulation.
Side Effects
Common Side Effects
Most side effects are related to CNS depression and tend to increase with higher doses:
- Drowsiness and excessive sedation
- Dizziness and lightheadedness
- Weakness or fatigue
- Unsteadiness, loss of balance, or poor coordination (ataxia)
- Confusion or memory impairment (anterograde amnesia)
Serious Side Effects
Contact a healthcare professional or seek emergency medical care immediately if you experience:
- Severe Respiratory Depression: Dangerously slow or shallow breathing.
- Paradoxical Reactions: Increased agitation, restlessness, irritability, aggression, or hallucinations.
- Suicidal Ideation or Depression: Worsening mood, depression, or thoughts of self-harm.
- Severe Allergic Reactions (Anaphylaxis): Swelling of the face, lips, tongue, or throat, accompanied by hives or trouble breathing.
Boxed Warnings & Key Precautions
FDA Black Box Warnings
- Risks from Concomitant Use with Opioids: Taking benzodiazepines like lorazepam alongside opioid medications or alcohol can result in profound sedation, severe respiratory depression, coma, and death.
- Abuse, Misuse, and Addiction: Use of lorazepam exposes individuals to the risk of abuse and addiction, which can lead to overdose or death even when taken as prescribed.
- Dependence and Withdrawal Reactions: Long-term use can lead to physical dependence. Abrupt discontinuation or rapid dose reduction can trigger life-threatening withdrawal symptoms, including seizures, tremors, psychosis, severe anxiety, and insomnia.
Contraindications
Do not use Lorazepam if you have:
- Known hypersensitivity to benzodiazepines.
- Acute narrow-angle glaucoma.
- Severe respiratory insufficiency or sleep apnea.
- Children under 12 years of age (safety and efficacy have not been established).
Pregnancy & Nursing Precautions
- Pregnancy: Lorazepam can cause fetal harm when administered during pregnancy. Use late in pregnancy may cause neonatal sedation, hypotonia (“floppy infant syndrome”), hypothermia, and withdrawal symptoms in the newborn.
- Lactation: Lorazepam is excreted in human milk and can cause sedation and feeding issues in nursing infants.
Major Drug Interactions
Medication / Substance | Interaction Risk | Precaution
- Opioid Pain/Cough Medications (e.g., oxycodone, morphine, codeine) Additive CNS and respiratory depression; risk of fatal overdose. Avoid combination unless explicitly directed and monitored by a doctor.
- Alcohol & Other CNS Depressants (e.g., sleep aids, barbiturates) Severe sedation, motor impairment, and respiratory collapse. Strictly avoid alcohol while taking lorazepam.
- Probenecid or Valproate Significantly delays lorazepam metabolism, increasing blood levels and side effects. Requires a dose reduction of lorazepam (typically by 50%).
- Clozapine Concomitant use can cause severe sedation, excessive salivation, and hypotension. | Use with extreme caution.