2C-T-21

4-(2-Fluoroethylthio)-2,5-dimethoxyphenethylamine

Aurora

Psychoactive Class

Chemical Class

2C-T-21 is a synthetic psychedelic of the substituted phenethylamine class and a member of the 2C-x family.¹ First described by Alexander Shulgin and colleagues in 1991¹ and later documented in his book PiHKAL,² it was derived from the systematic modification of the mescaline molecule. Distinguished by its fluoroethyl thioether substitution at the 4-position,¹² it remains a relatively obscure research chemical with limited documentation regarding its effects and safety profile.

Dosage & Duration

Dosage

Threshold~3 mg

Light3-5 mg

Moderate5-8 mg

Strong8-12 mg

Heavy12+ mg

Oral administration required. Non-oral routes carry substantial risk of severe adverse effects, including vomiting, dangerous physiological responses, and potentially fatal outcomes.

Duration

Onset30-90 minutes

Peak3-4 hours

Offset2-3 hours

After Effects2-4 hours

Total7-12 hours

Subjective Effects

The experience comes on very gradually, typically taking an hour to become noticeable and reaching full intensity by the end of the second hour. It is generally described as a gentle, warm, and non-threatening material characterized by clear thinking, enhanced communication, and a growing sense of closeness with others. Visuals are comparatively subdued, and the compound is repeatedly noted as easy on the body, though higher doses bring a considerable push of energy that can feel restless.

Physical

The body feeling is warm and energetic, generally safe and comfortable, though higher doses produce a push of energy accompanied by restlessness. Chills can occur during onset, along with yawning and ear-popping; appetite effects vary, with decreased appetite reported by some and unusual hunger by others.

Muscle tension

Autonomic

Pupil dilation

Stimulation

Cognitive

The headspace is notably clear and communicative, with empathy, insight, and a softening of the ego rather than dramatic alterations of consciousness. Mood is generally warm and peaceful, though it can occasionally turn faintly grim, and confusion is possible.

Confusion

Emotional

Enhancements

Visual

Visuals are present but understated, described in one account as not too pronounced.

Tactile

Tactile enhancement

Reagent Testing

Loading reagent data

Expected colorimetric results are being prepared.

Pharmacology

Pharmacodynamics

2C-T-21 acts as a partial agonist at the serotonin 5-HT2A receptor with high affinity (Ki = 27 nM),³ which is believed to underlie its psychedelic effects. It produces the head-twitch response in rodents, a behavioral proxy for psychedelic activity.³ Due to its structural similarity to 2C-T-2 and 2C-T-7, 2C-T-21 is also speculated to possess monoamine oxidase inhibitor (MAOI) properties, though this has not been confirmed.

Pharmacokinetics

Very little data exists regarding the metabolism of 2C-T-21. It has been hypothesized that fluoroacetate, a toxic compound, may be produced as a metabolite.

Interactions

Dangerous

Highest risk

These combinations are considered extremely harmful and should always be avoided. Reactions to these drugs taken in combination are highly unpredictable and have a potential to cause death.

AMTLithiumPCP

Unsafe

Avoid

There is considerable risk of physical harm when taking these combinations, they should be avoided where possible.

AmphetaminesCocaineDXMTramadol

Caution

Use caution

These combinations are not usually physically harmful, but may produce undesirable effects, such as physical discomfort or overstimulation. Extreme use may cause physical health issues. Synergistic effects may be unpredictable. Care should be taken when choosing to use this combination.

2C-x compounds5-MeO-xxT tryptaminesCannabisDOx compoundsMAOIsMDMAMescalineMXENBOMe compounds

TripSit

Tolerance

Full Tolerance

Develops almost immediately after ingestion.

Baseline Reset

Approximately 7 days in the absence of further consumption

Half Tolerance

Approximately 3 days

Cross Tolerance

Serotonergic psychedelics

Harm Potential

Addiction & Dependence

Psychological

Extremely Low

2C-T-21 is not generally associated with compulsive use; repeated experiences may lessen a person's interest in taking it again. Its use is typically self-limiting.

Toxicity

Multi-organ (Brain, Heart, Lungs, Gonads)

If the hypothesized fluoroacetate metabolite theory is correct, sub-lethal doses may theoretically cause damage to tissues with high metabolic demands; this remains unconfirmed in human studies and should not be assumed to occur at typical doses.

Seizure Risk

A tonic-clonic seizure was documented in the one fatal case, which involved an unknown but presumably very high dose.⁵ These symptoms are consistent with fluoroacetate poisoning.⁴ Seizure risk at typical doses (8-12 mg) is unknown due to limited human data.

History & Culture

Discovery and Synthesis

2C-T-21 was first synthesized by Alexander Shulgin, representing the final compound in the 2C-T series to be completed. Shulgin and colleagues first described the substance in scientific literature in 1991,¹ with detailed documentation appearing in his book

Legality

By Country

United StatesUnscheduled (Analogue Act applies)

Not specifically scheduled under the Controlled Substances Act. However, due to structural similarity to 2C-T-7, possession or sale intended for human consumption may be prosecuted under the Federal Analogue Act as a Schedule I equivalent. In 2004, a chemical supplier was federally indicted for distributing 2C-T-21 as a controlled substance analogue,⁷ subsequently pleading guilty in March 2005.

CanadaSchedule III (CDSA)

Became a controlled substance under Schedule III of the Controlled Drugs and Substances Act on October 31, 2016.⁸

SwitzerlandControlled (Verzeichnis E)

Regulated as a phenethylamine derivative under Verzeichnis E point 130 of the Betäubungsmittelverzeichnisverordnung. Exemptions exist for legitimate scientific or industrial applications.

AustriaIllegal (NPSG)

Possession, production, and sale are prohibited under the Neue-Psychoaktive-Substanzen-Gesetz (New Psychoactive Substances Act).

GermanyControlled (NpSG)

Regulated under the Neue-psychoaktive-Stoffe-Gesetz (New Psychoactive Substances Act) since November 26, 2016.⁹ Production, importation for market placement, administration to others, marketing, and trading are punishable offenses.¹⁰ Possession is technically illegal but not subject to criminal penalties.¹¹

United KingdomClass A

Controlled as a Class A substance under the Misuse of Drugs Act 1971 due to the phenethylamine catch-all clause.¹² Class A drugs carry the most severe penalties, including up to 7 years imprisonment for possession and life imprisonment for supply.

References

Source Pages

Citations

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2C-T-21

4-(2-Fluoroethylthio)-2,5-dimethoxyphenethylamine

Aurora

Psychoactive Class

Psychedelic Hallucinogen

Chemical Class

2C-X Phenethylamine (substituted)