2F-NENDCK (short for 2-fluoro-N–ethylnordeschloroketamine) is a novel dissociative drug that was detected at the CanTEST health and drug checking service as well as a forensic laboratory in China.1,2 After its identification by researchers at the Australian National University, 2F-NENDCK was initially called 2-fluoro-2’-oxo-PCE after which it became colloquially known as “CanKet” as in “Canberra ketamine”.1 Novel synthetic drugs like 2F-NENDCK are commonly referred to as “designer drugs” or “research chemicals”. These drugs often have very little research into their safety and effects on humans, which is indeed the case for 2F-NENDCK.
At CanTEST, 2F-NENDCK has been found numerous times in samples that were expected to be ketamine.3,4 According to CanTEST’s final evaluation, only 57% of the 81 samples expected to be ketamine actually contained ketamine as of April 2023.5 The remaining 43% of the 81 samples contained other dissociative drugs, including 2F-NENDCK, 2F-DCK, and tiletamine (a veterinary dissociative anaesthetic), as well as other psychoactive and non-psychoactive compounds.3 If you suspect your ketamine may be adulterated or contain a different drug entirely, consider taking a small sample to a drug checking service such as CanTEST. Ketamine testing kits may also be able to differentiate between ketamine and 2F-NENDCK.
2F-NENDCK belongs to a class of drugs called arylcyclohexylamines, which also includes ketamine. In fact, the chemical structure of 2F-NENDCK is almost identical to ketamine (spot the difference?). Despite the similarities, small differences in chemical structure can lead to relatively big differences in the pharmacology, toxicity, and subjective effects of drugs.6 For example, PCP (phencyclidine) and 3-HO-PCP are both members of the arylcyclohexylamine class, with 3-HO-PCP only differing at one position in its chemical structure.7 Despite this small difference, 3-HO-PCP is more potent than PCP, has a slightly shorter duration of effects, and interacts with μ-opioid receptors to a much greater extent than PCP, likely causing differences in its subjective effects and safety.7,8,9
While the risk profile of 2F-NENDCK may share similarities with ketamine, the unique effects, short-term risks, and long-term risks (if any) of 2F-NENDCK are still uncertain. Long-term ketamine use is known to cause kidney and bladder problems with symptoms similar to a urinary tract infection.10 This has been called ketamine bladder syndrome or ketamine-induced cystitis.10 It is unknown whether long-term or even short-term use of 2F-NENDCK can affect the kidneys and bladder in the same way or to what extent it does so. If you are experiencing symptoms of ketamine bladder syndrome, consider visiting a non-judgmental health professional such as the GP or nurse at the CAHMA clinic.
The subjective effects and pharmacology of 2F-NENDCK have not been formally studied. However, people who have previously used ketamine report similar effects but with some noticeable differences.6,11 One user reported the following differences compared to ketamine:11
Felt more intoxicating.
Effects seemed stronger but plateaued sooner.
Vision was affected more.
Stronger sense of disorientation.
Felt more of a hangover the next day.
An anonymous user who was interviewed by VICE World News described the effects of 2F-NENDCK as “very similar to ketamine, but not as deep or introspective” and “the ‘happy’ feeling was lacking a little bit.”6 The effects may also last longer than ketamine.4
For an overview of the effects of ketamine, please visit: link to ketamine article.
Since the potency of 2F-NENDCK has not been documented, it is especially important to start with a low dose and wait before redosing (start low and go slow). It may be useful to take a smaller dose of 2F-NENDCK and work up to the desired effects/intensity, rather than simply matching your preferred dose of ketamine. This may reduce the risk of an accidental overdose. The following is a rough guide for dosing ketamine (not 2F-NENDCK):12
LOW DOSE – 20-50 mg
MEDIUM DOSE – 50-125 mg
STRONG DOSE – 125-175 mg
HEAVY DOSE, POSSIBLE ANAESTHESIA – 175+ mg
Like ketamine, the strength of a dose of 2F-NENDCK likely depends on the route of administration with injection possibly being stronger than snorting or oral administration.
2F-NENDCK Overdose and “K-Hole”
The risks associated with overdosing 2F-NENDCK or mixing it with other drugs are largely unknown. 2F-NENDCK possibly causes anaesthesia at high doses like ketamine, which could cause loss of coordination, motor control or consciousness.13 Additionally, mixing 2F-NENDCK with other depressants, including alcohol, GHB, and opioids, may be particularly dangerous since the combination could increase the risk of vomiting, loss of coordination, and unconsciousness.12 If a person falls unconscious while combining these substances, place them in the recovery position to prevent vomit aspiration.12 2F-NENDCK may have unpredictable effects when mixed with other drugs or prescription medications.
Some ketamine users seek a high-dose experience known as a “k-hole”, which consists of complete dissociation and partial anaesthesia but allows the user to retain some degree of consciousness and memory of the experience.13 It is unknown whether 2F-NENDCK can produce a similar “k-hole” experience and what the correct dose required to achieve this would be. Taking very high doses of 2F-NENDCK could cause other unpredictable and possibly dangerous effects.