Phenergan vs. Lorazepam


We compare the side effects and drug effectiveness of Phenergan and Lorazepam. The study is created by eHealthMe based on reports of 179,184 people who take Phenergan and Lorazepam, and is updated regularly.

What's eHealthMe?

eHealthMe is a health data analysis company based in Mountain View, California. eHealthMe monitors and analyzes the outcomes of drugs and supplements that are currently on the market. The results are readily available to health care professionals and consumers.

eHealthMe has released original studies on market drugs and worked with leading universities and institutions such as IBM, London Health Science Centre, Mayo Clinic, Northwestern University and VA. eHealthMe studies have now been referenced in over 500 peer-reviewed medical publications.

How we gather our data?

Healthcare data is obtained from a number of sources including the Food and Drug Administration (FDA). This information is aggregated and used to produce personalized reports that patients can reference.

The information that eHealthMe collects includes:

  • Side effects (including severity and how people recover from them)
  • Associated conditions or symptoms
  • Drug effectiveness
  • Demographic data regarding drug use

How the study uses the data?

The study is based on promethazine hydrochloride and lorazepam (the active ingredients of Phenergan and Lorazepam, respectively). Other drugs that have the same active ingredients (e.g. generic drugs or brand names) are also considered.

What is Phenergan?

Phenergan has active ingredients of promethazine hydrochloride. It is often used in nausea. (latest outcomes from Phenergan 20,483 users)

What is Lorazepam?

Lorazepam has active ingredients of lorazepam. It is often used in stress and anxiety. (latest outcomes from Lorazepam 95,213 users)

How to use the study?

Patients can bring a copy of the report to their healthcare provider to ensure that all drug risks and benefits are fully discussed and understood. It is recommended that patients use the information presented as a part of a broader decision-making process.

On Feb, 24, 2019

179,184 people who take Phenergan and Lorazepam are studied.

Number of reports submitted per year:

Phenergan vs Lorazepam drug comparison reports.

Drugs in this study:

  • Lorazepam (lorazepam)
  • Phenergan (promethazine hydrochloride)

Most common side effects:

  1. Fatigue (feeling of tiredness)
  2. Dyspnoea (difficult or laboured respiration)
  3. Diarrhoea
  4. Pain
  5. Headache (pain in head)
  6. Drug Ineffective
  7. Depression
  8. Asthenia (weakness)
  9. Dizziness
  10. Pyrexia (fever)
  1. Pain
  2. Diarrhoea
  3. Fatigue (feeling of tiredness)
  4. Headache (pain in head)
  5. Dyspnoea (difficult or laboured respiration)
  6. Abdominal Pain
  7. Pyrexia (fever)
  8. Asthenia (weakness)
  9. Depression
  10. Back Pain

Most common side effects experienced by people in long term use:

  1. Depression
  2. Headache (pain in head)
  3. Pain
  4. Fatigue (feeling of tiredness)
  5. Dyspnoea (difficult or laboured respiration)
  6. Emotional Distress
  7. Suicidal Ideation
  8. Drug Ineffective
  9. Drug Withdrawal Syndrome (interfere with normal social, occupational, or other functioning. are not due to another medical condition, drug use, or discontinuation)
  10. Suicide Attempt
  1. Pain
  2. Chronic Kidney Disease
  3. Diarrhoea
  4. Fall
  5. Chest Pain
  6. Fatigue (feeling of tiredness)
  7. Drug Ineffective
  8. Malaise (a feeling of general discomfort or uneasiness)
  9. Depression
  10. Pyrexia (fever)

Drug effectiveness:

  • not at all: 2.76 %
  • somewhat: 22.06 %
  • moderate: 35.92 %
  • high: 28.28 %
  • very high: 10.98 %
  • not at all: 3.32 %
  • somewhat: 21.01 %
  • moderate: 32.31 %
  • high: 30.45 %
  • very high: 12.9 %

Do you take Phenergan or Lorazepam?

You are not alone:

Related publications that referenced our studies

Related studies:

Compare Phenergan with similar drugs
Compare Lorazepam with similar drugs

Recent updates

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WARNING: Please DO NOT STOP MEDICATIONS without first consulting a physician since doing so could be hazardous to your health.

DISCLAIMER: All material available on is for informational purposes only, and is not a substitute for medical advice, diagnosis, or treatment provided by a qualified healthcare provider. All information is observation-only, and has not been supported by scientific studies or clinical trials unless otherwise stated. Different individuals may respond to medication in different ways. Every effort has been made to ensure that all information is accurate, up-to-date, and complete, but no guarantee is made to that effect. The use of the eHealthMe site and its content is at your own risk.

You may report adverse side effects to the FDA at or 1-800-FDA-1088 (1-800-332-1088).

If you use this eHealthMe study on publication, please acknowledge it with a citation: study title, URL, accessed date.