Home Wiki Studies Forum Groups Blog Video Images News Chat
Go Back   Drugs Forum > Wiki Articles > Drug Articles
Mark Forums Read
Register Tags


Drug Articles Articles about drugs


Lofexidine (Britlofex) is an alpha2-adrenergic receptor agonist commonly used to alleviate some of the physical symptoms of opiate withdrawal by decreasing the release of norepinephine and epinephrine. It helps to lessen physical withdrawal symptoms such as chills, sweating and cramps, but will not eliminate the symptoms. It will not stop cravings either.[1] Lofexidine effects blood pressure less than clonidine[2], so is safer for detox outside of an inpatient setting I.E. home detox. [3][4]


[top]Introduction to Lofexidine

[top]Using Lofexidine

THe initial dosage should be 0.8mg per day in divided doses. The dosage may be increased by increments of 0.4 to 0.8mg per day up to a max of 2.4mg daily. Max single dose should not exceed 0.8mg. [5]The amount required will depend on a number of factors. For example, those who are undergoing an acute detox (cold turkey) will need a higher dose than those commencing lofexidine treatment at the end of a taper. The typical duration of treatment for a detox without opiate substitution is 7-10 days, however some user made guides recommend is use for a longer duration, especially with "cold turkey" or steep taper detoxes [6] It is recommended to gradually reduce the dose, rather than stopping suddenly, to avoid the risk of rebound hypertension, which not only could be unpleasant, but potentially harmful to health

[top]Ways of Administration

Lofexidine is administered orally, as the hydrochloride salt and is available as 0.2mg tablets.

[top]Effects of Lofexidine

[top]Combinations with Lofexidine

Naltrexone may be used in combination with lofexidine as part of an inpatient detoxification treatment. In one study, lofexidine was compared to a combination of lofexidine and nalrexone for detox purposes. Withdrawal symptoms were significantly less severe on days 47, and 913, in the naltrexone/lofexidine combination group than lofexidine alone[7] Lofexidine in combination with naltrexone also reduced post detox relapses and reduced the effect of cravings caused by stress, stress-induced opiate craving, and negative emotions [8]
Naloxone has also been used, with similar results. Overall abstenance rates were not different for naloxone/lofexidine versus lofexidine alone, but reported/subjective withdrawal symptoms were lower for the combination group[9]

Lofexidine may also be user in conjunction with opiates as part of a taper [10] however when used as part of a slow taper is not shown to significantly increase success rates, and appears to be more useful for quick tapers or cold turkey detoxes. Useful guides to utilising lofexidine in methadone/buprenorphine tapers can be found in the thread: https://drugs-forum.com/forum/showthread.php?t=76991

According to NHS guidlines, the following medications may also be prescribed to offer further symptomatic relief, for no longer than 21 days[11]:
  • Diazepam: For agitation
  • Zopiclone: For insomnia
  • Buscopan: For stomach cramps
  • Ibuprofen: For analgesia
  • Loperamide: For diarrhoea

[top]Different Uses for Lofexidine

[top]Pharmacology of Lofexidine

During opiate withdrawal, levels of catacholeamines like adrenaline and noradrenaline are significantly elevated, and are responsible for some of the physical effects of opiate withdrawal. Lofexidine stimulates receptors in the brain that monitor the levels of adrenaline and noradrenaline in the blood. The brain believes that catecholamine levels are higher than they really are, causing signals to be sent to the adrenal medulla, which is part of the adrenal glands that sit above the kidneys. The signals cause the adrenal glands to lower catecholamine production, which lowers the amount in the bloodstream. This lowers the heart rate and blood pressure, offering some relief from the physical withdrawal symptoms

Lofexidine is a structural analogue of clonidine. It is an imidazoline with a high affinity for α2-adrenergic receptor subtypes. This makes it less likely to cause hypotension than non-selective α2-adrenergic agonists [12]
When taken orally lofexidine has a very high bioavailability, in the range of around 90%. Average time to peak plasma concentration is 3 hours, but can vary from 2-5. Half life is approximately 11 hours, meaning that a steady state for plasma concentration is reached after approx 2 days (55hours)[13][14]
There are few studies available on the metabolism and excretion of lofexidine, but one study using radiolabeled C14 showed "significant
hepatic metabolism [glucuronidation] with four metabolites detected. The glucuronide metabolites accounted for 50% of those identified. Approximately 10% of the drug appears unchanged in the urine."[15]The main metabolite found was 2,6-dichlorophenol, which was excreted in urine as "two O-glucuronic acid conjugates" [16]

LD50 (mg/kg) (as the hydrochloride) [1] :
74-147 orally (rat, mice, dog); 8-18 intravenously (rat, mice, dog)

[top]Chemistry of Lofexidine

Systematic (IUPAC) name:(RS)-2-[1-(2,6-dichlorophenoxy)ethyl]-4,5-dihydro-1H-imidazole
Synonyms:2-[1-(2,6-dichlorophenoxy)ethyl]-2-imidazoline; MDL-14042A, Ba-168, BritLofex, Lofetensin (hydrochloride)
Molecular Formula:C11H12Cl2N2O, C11H12Cl2N2O.HCl
Molar mass:259.13 g/mol, 295.59 g/mol (hydrochloride)
CAS Registry Number:31036-80-3, 21498-08-8 (hydrochloride)
Melting Point:126-128C; 221-223C, also reported 230-232C (hydrochloride)
Boiling Point:no data
Flash Point:no data
Solubility:Hydrochloride very soluble in water, ethanol; sligthly soluble in isopropanol; practically insoluble in ether
Additionnal data:none
Notes:Hydrochloride crystallized from ethanol + ether or isopropanol

[top]The Dangers of Lofexidine

Lofexidine should be used with caution if you suffer from severe coronary insufficiency, recent myocardial infarction, cerebrovascular disease or chronic renal failure and in patients with bradycardia or hypotension.[17]
Lofexidine should not be taken if you are pregnant or breast feeding or have underlying psychosis or mental health[18]

Lofexidine can cause hypotension and bradycardia, though not as severely as clonidine, so caution should be taken when standing up quickly, getting out of a hot bath, or any situation in which you are chaning posture quickly. If you feel dizzy, light headed or faint, do not drive or operate machinery.

As Lofexidine may cause drowsiness and sedation, interactions may occur when taken in combination with
alcohol, sedatives, anti-hypertensive agents and tricyclic antidepressants. Particular risk arises when pharmacokinetic and pharmacodynamic interactions may occur e.g. concurrent use of alcohol or sedatives.[19]

Overdosage may cause hypotension, bradycardia and sedation.[20]

[top]Summary of side effects

BritLofex tablets may sometimes cause the following:
dry mouth or throat
dry nose
light-headedness or dizzyness upon standing
slow heart beat

[top]Legal Status of Lofexidine

Not controlled. Prescription only medicine


Lofexidine has not yet been approved by the FDA for use in the USA, however it is undergoing phase III trials [22]



Lofexidine has been used in an estimated 20 000[23] detoxifications over 13 years in the UK, where it is marketed by Britannia Pharmaceuticals as Britlofex. It is a prescription only medication and is approved for home and inpatient detox


[top]Popularity of lofexidine over time

[top]The Latest Lofexidine Threads

  Article / Page Starter Last Post Comments Views
26-10-2016 18:41
by JarvyJarvison Go to last post
3 74
26-10-2016 18:24
by ACertainRatio Go to last post
1 19
26-10-2016 17:03
by JarvyJarvison Go to last post
6 143
26-10-2016 16:48
by JarvyJarvison Go to last post
10 304
26-10-2016 15:27
by Phencyclidine Go to last post
41 112,205
26-10-2016 04:44
by bamackc Go to last post
33 1,230
26-10-2016 04:14
by FastFifty Go to last post
30 1,276
26-10-2016 03:41
by prescriptionperil Go to last post
58 2,821


  1. ^ http://www.patient.co.uk/medicine/Lofexidine.htm
  2. ^ http://www.ncbi.nlm.nih.gov/pubmed/6890374
  3. ^ https://drugs-forum.com/forum/local_links.php?action=jump&catid=133&id=4559
  4. ^ http://www.sciencedirect.com/science/article/pii/S0376871698000404
  5. ^ http://www.medicines.org.uk/emc/medicine/7119/SPC/BritLofex+Tablets+0.2mg/#POSOLOGY
  6. ^ https://drugs-forum.com/forum/showthread.php?t=76991
  7. ^ http://www.sciencedirect.com/science/article/pii/S0376871699001167
  8. ^ https://drugs-forum.com/forum/showthread.php?t=91820
  9. ^ Bearn J, Bennet J, Martin T, Gossop M, Strang J The impact of naloxone/lofexidine combination
    treatment of the opiate withdrawal syndrome. Addiction Biology 2001; 6(2): 147-156
  10. ^ https://drugs-forum.com/forum/showthread.php?t=76991&highlight=lofexidine
  11. ^ http://www.nhft.nhs.uk/mediaFiles/downloads/30503881/MMG025.pdf.pdf
  12. ^ Cox, S. and Alcorn, A. (1995) Lofexidine and opioid withdrawal. Lancet, 345, 13851386.
  13. ^ http://www.ncbi.nlm.nih.gov/pubmed/18393298
  14. ^ http://www.medicines.org.uk/emc/medicine/7119/SPC/BritLofex+Tablets+0.2mg/#PHARMACOKINETIC_PROPS
  15. ^ http://www.nacd.ie/publications/LofexidineReport.pdf
  16. ^ http://www.ncbi.nlm.nih.gov/pubmed/6880242
  17. ^ http://www.medicines.org.uk/emc/medicine/7119/SPC/BritLofex+Tablets+0.2mg/#INTERACTIONS
  18. ^ http://www.nhft.nhs.uk/mediaFiles/downloads/30503881/MMG025.pdf.pdf
  19. ^ http://alcalc.oxfordjournals.org/content/36/5/426.full
  20. ^ http://www.drugbank.ca/drugs/DB04948
  21. ^ https://drugs-forum.com/forum/showthread.php?t=92535
  22. ^ http://www.solsticeneuro.com/docs/USW%20RELEASE%20-%20FINAL%20REV%2010.10.pdf
  23. ^ Strang, J., Bearn, J. and Gossop, M. (1999) Lofexidine for opiate detoxification: review of recent randomised and open controlled trials. American Journal on Addictions 8, 337348.

[1] Merck Index, fifteenth edition (2013)

Contributors: John_bob, Alfa, Docta, davestate
Created by davestate , 12-04-2012 at 21:37
Last edited by Docta, 12-10-2014 at 08:42
Last comment by John_bob on 09-05-2014 at 13:03
4 Comments, 18,596 Views

Share this on:

britlofex, detox, lofexidine, withdrawal
Page Tools

Posting Rules
You may not create new articles
You may not edit articles
You may not protect articles

You may not post comments
You may not post attachments
You may not edit your comments

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Similar Pages
Article Page Starter Forum Comments Last Post
Davestates testing wiki: Irish drug laws davestate Wiki Testing Grounds 0 12-04-2012 13:37

Sitelinks: Information:

All times are GMT +1. The time now is 20:15.

Copyright: SIN Foundation 2003 - 2014, All rights reserved