Taking Xanax and Klonopin Together: What Are the Adverse Effects?

diazepam pills
Getty Images

Are you wondering whether it's a good idea to take both Xanax (alprazolam) and Klonopin (clonazepam) for anxiety and panic attacks? You might be concerned about what potential side effects there might be when you take both drugs together. Learn more about the pros and cons so you know what to discuss with your doctor. 

Possible Side Effects

Xanax and Klonopin belong to a class (or type) of medications known as benzodiazepines. Benzodiazepines are commonly used to treat anxiety and help many people who have a panic disorder.

Both of these medications can cause undesirable side effects in some people, including:

  • Abdominal distress
  • Abnormal involuntary movement
  • Agitation
  • Allergic reaction
  • Anxiety
  • Appetite decreased
  • Appetite increased
  • Confusion
  • Constipation
  • Coordination abnormal
  • Depression
  • Dermatitis
  • Diarrhea
  • Dizziness
  • Dream abnormalities
  • Dry mouth
  • Edema
  • Fatigue
  • Headache
  • Hypotonia
  • Insomnia
  • Irritability
  • Libido decreased
  • Libido increased
  • Memory impairment
  • Menstrual disorders
  • Nausea
  • Nervousness
  • Palpitations
  • Salivation increased
  • Sleepiness
  • Slurred speech
  • Tremor
  • Upper respiratory tract infection
  • Vision disorders
  • Weakness
  • Weight gain
  • Weight loss

Also, these drugs can become less effective over time, and some people increase the dose to help relieve anxiety. However, such increases in the dosage can lead to dependence and make it difficult to decrease the medication or stop it.

Since Xanax and Klonopin belong to the same drug class and are similar medications, they have similar adverse effects. Taking both of them at the same time may make it more likely that you will experience an adverse effect.

How Long to Take Each Drug

You may want to speak with your physician about how long you will be on Xanax and Klonopin and if it will be necessary for you to continue to take both medications. Xanax stays in your body for less time than Klonopin. If you start by taking Xanax alone, your physician may start the Klonopin to help you better control your anxiety and panic attacks. If it helps, your physician may recommend that you decrease the dosage of your Xanax and wean yourself off it.

Drug Interactions

You also need to be aware that both Xanax and Klonopin interact with many other medications. It is important that you tell your physician and your pharmacist about all medications that you are using. This includes prescription drugs, over-the-counter drugs, and even supplements such as vitamins and herbal remedies.

Both medications also interact with grapefruit juice, which may increase the amount of the medication that gets into your body. Drinking grapefruit juice could increase your risk of adverse effects, so avoid that beverage completely to be safe.

Post-Traumatic Stress Disorder (PTSD)

Anxiety and panic attacks can be symptoms of post-traumatic stress disorder (PTSD), a condition that is common among veterans who return from Iraq and Afghanistan. If you are concerned that you may have PTSD, please speak with your physician to make sure that you get properly diagnosed and receive access to appropriate services. For instance, your doctor may recommend that you receive another treatment such as psychological therapy in addition to taking any medication(s).

Also be aware that people who suffer from anxiety and people who have PTSD are more likely than the general population to abuse substances, so keep a close eye on your intake of alcohol and recreational drugs because you might need to seek out separate treatment for that.

6 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. U.S. National Library of Medicine. KLONOPIN- clonazepam tablet. DailyMed.

  2. U.S. National Library of Medicine. XANAX- alprazolam tablet. DailyMed.

  3. National Institutes of Health National Institute on Drug Abuse. Benzodiazepines and Opiods.

  4. Ait-Daoud N, Hamby AS, Sharma S, Blevins D. A review of alprazolam use, misuse, and withdrawalJournal of Addiction Medicine. 2018;12(1):4-10. doi:10.1097/ADM.0000000000000350

  5. Jargin S. Grapefruit: perspectives in nutrition and pharmacologyJ Intercult Ethnopharmacol. 2017;6(3):1. doi:10.5455/jice.20170511061624

  6. Substance Abuse and Mental Health Services Administration. National Helpline.

Additional Reading
  • Tsutaoka B. Chapter 31. Benzodiazepines. In: Olson KR. eds. Poisoning & Drug Overdose, 6e. New York, NY: McGraw-Hill; 2012.

By Michael Bihari, MD
Michael Bihari, MD, is a board-certified pediatrician, health educator, and medical writer, and president emeritus of the Community Health Center of Cape Cod.