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How long does lofexidine typically take to work?

Medically reviewed by Sally Chao, MD. Last updated on Jan 23, 2023.

Official answer


Lofexidine starts to work shortly after taking a single dose by mouth. The drug reaches maximum concentration in your blood in 3 to 5 hours. Lofexidine is a non-opioid prescription drug used to manage the symptoms of sudden withdrawal from opioid drugs. Opioid withdrawal symptoms include:

  • Muscle aches and pains
  • Sweating
  • Yawning
  • Runny eyes and nose
  • Stomach cramps
  • Nausea and vomiting
  • Diarrhea

Lofexidine was approved in 2018 by the United States Food and Drug Administration and is the only non-opioid, non-addictive medication approved to treat multiple symptoms of opioid withdrawal in adults. It is available in tablet form and sold under the brand name Lucemyra. It is just as safe and effective as other drugs and may have fewer side effects.

You can begin taking lofexidine immediately after you stop taking opioid drugs. Symptoms of opioid withdrawal most commonly peak 5 to 7 days after quitting opioid drugs. It has been found that lofexidine is most effective when given the maximum dose within that range.

A typical dose of lofexidine is three tablets taken four times daily. There should be 5 or 6 hours in between each dose. You can take lofexidine with or without food. You should not take more than 4 tablets at a time, or 16 tablets in one day. People with liver or kidney problems may need to take a lower dose, depending on their condition.

Lofexidine can be taken for up to 14 days as needed to manage symptoms. The dose is gradually reduced over 2 to 4 days as you begin to feel better.

Lofexidine can cause a decrease in blood pressure and pulse. You may also be more likely to faint while taking lofexidine. You may not be able to take lofexidine if:

  • You have severe heart problems.
  • You have severe kidney problems.
  • You are taking certain medications, including beta blockers and ACE inhibitors.
  1. Food and Drug Administration (FDA). Prescribing information: Lucemyra (lofexidine) tablets, for oral use. Available at: [Accessed on January 21, 2021].
  2. Rehman SU, Maqsood MH, Bajwa H, Tameez Ud Din A, Malik MN. Clinical efficacy and safety profile of lofexidine hydrochloride in treating opioid withdrawal symptoms: A review of literature. Cureus. 2019 June 4;11(6):e4827. doi: https://10.7759/cureus.4827. [Accessed on January 21, 2021].
  3. Pergolizzi JV, Annabi H, Gharibo C, et al. The role of lofexidine in management of opioid withdrawal. Pain Ther. 2019 June 8;67–78. doi: [Accessed on January 21, 2021].
  4. U.S. National Library of Medicine. Opiate and opioid withdrawal. May 10, 2020. Available at: [Accessed on January 26, 2021].

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