ETH-LAD

# Research Output: ETH-LAD

**Substance:** ETH-LAD (N⁶-ethyl-6-norlysergic acid diethylamide; 6-ethyl-6-nor-LSD)
**PSX ID:** PSX-0184
**Research Date:** 2026-04-26
**Provenance ID:** 95395d14-0774-487a-9943-09ec51398aaf

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## Chemical Identity

**Verified via PubChem CID 44457783:**

| Property | Value | Source |
|---|---|---|
| PubChem CID | 44457783 | PubChem (api_verified) |
| IUPAC Name | (6aR,9R)-N,N,7-triethyl-6,6a,8,9-tetrahydro-4H-indolo[4,3-fg]quinoline-9-carboxamide | PubChem |
| Molecular Formula | C₂₁H₂₇N₃O | PubChem |
| Molecular Weight | 337.5 g/mol | PubChem |
| InChIKey | MYNOUXJLOHVSMQ-DNVCBOLYSA-N | PubChem |
| CAS Number | 65527-62-0 | Chemsrc [Ref 29] |

**Notes on brief discrepancies:**
- The brief seed data was missing: SMILES, molecular formula, molecular weight, InChIKey, PubChem CID, and CAS number. All have now been retrieved and verified via PubChem (api_verified) except CAS (web_retrieved).
- The IUPAC name in the brief matches the PubChem entry exactly: **(6aR,9R)-N,N,7-triethyl-6,6a,8,9-tetrahydro-4H-indolo[4,3-fg]quinoline-9-carboxamide** — confirmed correct.
- SMILES string was not returned by the PubChem API call; the generation agent should retrieve this from PubChem directly using CID 44457783.
- The brief's systematic name listed under "Systematic name" matches the IUPAC name — correct.

**Structural context:** ETH-LAD is the N⁶-ethyl analog of nor-LSD (N-demethyl-LSD). The N⁶ position refers to the nitrogen at position 6 of the ergoline ring system (the nitrogen that bears a methyl group in natural LSD). Replacing this methyl with an ethyl group yields ETH-LAD. AL-LAD (the N⁶-allyl analog) is the structurally closest well-characterized comparator. The compound is a chiral molecule; the biologically active stereoisomer has the (6aR,9R) configuration, matching the d-lysergic acid scaffold common to all active lysergamides.

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## Pharmacology

### Primary Mechanism of Action

ETH-LAD belongs to the lysergamide class of serotonergic psychedelics. Its primary mechanism is agonism/partial agonism at the serotonin 5-HT₂A receptor, particularly on apical dendrites of neocortical pyramidal cells in cortical layer V (Nichols 2016 [Ref 16]; Cummins et al. 2025 [Ref 15]).

The 5-HT₂A mechanism was established for the lysergamide class through a range of studies. Halberstadt et al. have repeatedly demonstrated that M100907 (a selective 5-HT₂A antagonist) completely abolishes the head-twitch response (HTR) induced by 1P-LSD (Brandt et al. 2016 [Ref 7]), AL-LAD, and LSZ (Brandt et al. 2017 [Ref 6]), confirming that 5-HT₂A activation is necessary and sufficient for the characteristic psychedelic behavioral signature in rodents. Holze et al. (2021 [Ref 21]) confirmed this in humans, demonstrating that ketanserin (5-HT₂A antagonist) fully blocked the subjective effects of 200 µg LSD.

ETH-LAD's binding to the 5-HT₂A receptor is predicted to share LSD's "EL2 lid" mechanism characterized by Wacker et al. (2017 [Ref 13]): the extracellular loop 2 closes over the bound ligand, creating exceptionally slow dissociation kinetics from both 5-HT₂A and 5-HT₂B receptors, contributing to prolonged receptor occupancy and extended duration of action.

### Receptor Binding Profile

No ETH-LAD-specific receptor binding study has been published in the accessible peer-reviewed literature. The following data require editorial flagging:

**⚠️ FLAG — Unverified Ki values:** A commercial supplier database (MedChemExpress) lists ETH-LAD receptor affinities as 5-HT₂A Ki = 5.1 nM, dopamine D1 Ki = 22.1 nM, dopamine D2 Ki = 4.4 nM. The primary source for these values could not be identified or verified through PubMed, OpenAlex, or Crossref searches. These values may derive from the Hoffman & Nichols (1985 [Ref 9]) original pharmacology study or from unpublished PDSP screening data. **These Ki values should not be cited without identifying the primary source.**

By class-level structural analogy with LSD (the direct parent compound):
- LSD's receptor profile includes: 5-HT₁A agonist, 5-HT₂A/2B/2C partial agonist, dopamine D₂ agonist (particularly at higher doses), TAAR₁ stimulation, and glutamatergic modulation (De Gregorio et al. 2016 [Ref 23]; Nichols 2016 [Ref 16]).
- The N⁶-ethyl modification in ETH-LAD replaces the N-methyl group; Hoffman & Nichols (1985 [Ref 9]) demonstrated that this substitution produces compounds 1.6–2.3× more potent than LSD in rat LSD-discrimination paradigms, with the N⁶-ethyl and N⁶-allyl analogs (ETH-LAD and AL-LAD) being the most potent.

### Potency Relative to LSD

In mouse HTR assays, the reference LSD ED₅₀ = 132.8 nmol/kg (C57BL/6J mice, IP; established across multiple studies in the Brandt/Halberstadt series [Refs 6, 7, 3]). ETH-LAD-specific HTR data have not been published.

In drug discrimination assays (rat, from Hoffman & Nichols 1985 [Ref 9]): ETH-LAD was approximately **1.6–2.3× more potent than LSD**, placing it among the most potent lysergamides studied. The N⁶-allyl analog (AL-LAD) showed comparable potency increases; by contrast, longer N⁶-alkyl chains reduced potency.

Shulgin (TiHKAL, 1997 [Ref 12]) described ETH-LAD as "a little more potent than LSD" in human subjective experience, broadly consistent with the preclinical data.

### 5-HT₁A Partial Agonism

LSD and by extension ETH-LAD function as partial agonists at 5-HT₁A receptors in the dorsal raphe nucleus (De Gregorio et al. 2016 [Ref 23]). This activity modulates serotonergic neurotransmission in a manner that may blunt some 5-HT₂A-mediated effects, as demonstrated in the context of 5-MeO-DMT analogs where 5-HT₁A blockade enhanced 5-HT₂A-mediated HTR responses. The 5-HT₁A partial agonism in the brief's characterization ("Serotonin 1A receptor partial agonist") is consistent with class-level evidence.

### Metabolism

Wagmann et al. (2019 [Ref 2]) established the in vitro metabolic fate of ETH-LAD using pooled human liver S9 fraction:

- **Primary metabolizing enzymes:** CYP1A2 and CYP3A4 (confirmed via recombinant human enzymes and inhibition experiments)
- **Predominant biotransformations:** N-dealkylation and hydroxylation, and combinations of these steps
- **Detection in urine:** Parent compound and metabolites were undetectable in rat urine following administration of expected recreational doses using standard urinalysis screening approaches
- This non-detectability has significant forensic and clinical toxicology implications: ETH-LAD intoxication would be difficult to confirm via routine urine drug screening

**1P-ETH-LAD prodrug relationship:** Brandt et al. (2017 [Ref 1]) demonstrated that 1-propionyl ETH-LAD (1P-ETH-LAD) undergoes hydrolysis to ETH-LAD when incubated with human serum at 37°C over 1–6 hours, with ETH-LAD still detectable at 24 hours. This strongly suggests 1P-ETH-LAD acts as an ETH-LAD prodrug in vivo. This mirrors the established prodrug relationships for 1P-LSD → LSD (Halberstadt et al. 2020 [Ref 5]).

### Pharmacokinetics

**⚠️ FLAG — No published human PK data for ETH-LAD.** The following is inferred by structural analogy from LSD, the direct parent:

LSD (Holze et al. 2021 [Ref 21]; Holze et al. 2022 [Ref 25]):
- Dose-proportional pharmacokinetics, first-order elimination
- Average plasma half-life: ~2.4 hours
- Duration of subjective effects: 6.7–11 hours depending on dose (25–200 µg)
- Time to peak: approximately 2 hours (consistent with Coney 2017 [Ref 8] finding of modal time to peak 2h for LSD analogues)

ETH-LAD is reported to have a duration of 8–12 hours orally in human use (Shulgin/TiHKAL [Ref 12]; Coney et al. 2017 [Ref 8] found modal duration 8 hours for LSD analogues collectively). Given ETH-LAD's higher drug discrimination potency vs LSD, if effects are experienced at lower absolute doses, effective duration may parallel LSD at equivalent effect levels.

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## History

### First Synthesis

ETH-LAD was first synthesized and reported in the scientific literature by **Niwaguchi, Nakahara, and Ishii** (1976 [Ref 24]) in their series "Studies on lysergic acid diethylamide and related compounds. IV. Syntheses of various amide derivatives of norlysergic acid and related compounds" published in *Yakugaku Zasshi* (Journal of the Pharmaceutical Society of Japan). This paper is in Japanese; the abstract is not available via PubMed.

### Preclinical Pharmacology

**Hoffman and Nichols (1985 [Ref 9])** at Purdue University published the pivotal pharmacological characterization of ETH-LAD and related N⁶-alkyl-norlysergic acid diethylamide derivatives in the *Journal of Medicinal Chemistry*. This study:
- Synthesized a series of N⁶-alkyl nor-LSD analogs (methyl through hexyl, plus allyl)
- Evaluated them in rat drug discrimination assays trained to discriminate LSD from saline
- Found the N⁶-ethyl (ETH-LAD) and N⁶-allyl (AL-LAD) analogs were 1.6–2.3× more potent than LSD
- Established the structure-activity relationship showing intermediate-length N⁶-alkyl chains optimize potency

### Human Use Documentation

**Alexander Shulgin** documented the first published account of ETH-LAD in humans in **TiHKAL: The Continuation** (1997 [Ref 12]), co-authored with Ann Shulgin. Entry #12 describes oral doses of 40–150 µg over 8–12 hours. Shulgin characterized the experience as distinctive for its gentleness relative to LSD — "a little more potent than LSD, but much less aggressive" — with mild visual alterations, maintained warmth and cognitive clarity, diuretic properties, and notably increased appetite (unlike LSD's typical appetite suppression). Shulgin also noted potential instability in solution over months, even under dark/frozen/anaerobic conditions.

### Emergence as NPS

ETH-LAD emerged as a commercially available **research chemical / novel psychoactive substance (NPS)** on online markets, with AL-LAD and LSZ appearing around 2013 (Brandt et al. 2017, Part II [Ref 6]). ETH-LAD and 1P-ETH-LAD were analytically characterized as emerging NPS by Brandt et al. (2017, Part III [Ref 1]), which noted that "limited analytical data for ETH-LAD were previously available" — indicating ETH-LAD's presence on the NPS market preceded this analytical work. 

Coney et al. (2017 [Ref 8]) using Global Drug Survey 2016 data (N = 96,894) found significant user populations for ETH-LAD, AL-LAD, and 1P-LSD, particularly in the UK and USA.

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## Subjective Effects

### Published Survey Data (Coney et al. 2017 [Ref 8])

The Coney et al. study used the Global Drug Survey 2016 and is the only published survey data directly addressing ETH-LAD user experience. Key findings for LSD analogues as a group (including ETH-LAD, AL-LAD, 1P-LSD):

- **Effects described as psychedelic** by 93% of users
- **Modal duration:** 8 hours (not significantly different from LSD)
- **Time to peak:** 2 hours (not significantly different from LSD)
- **Route:** 99% oral administration
- **Source:** 55% obtained online
- **Prior LSD experience:** 91% had also tried LSD
- **Compared to LSD:** significantly **lower** ratings for pleasurable high, strength of effect, comedown, urge to use more drugs, value for money, and perceived risk of harm

The lower ratings relative to LSD are consistent with reports that these analogs — at equivalent mass doses — produce less intense effects, though this must be interpreted in the context that users may not have been dose-adjusting for ETH-LAD's greater mass-per-effect potency vs LSD.

### Shulgin Self-Report (TiHKAL 1997 [Ref 12])

Shulgin's first-person account describes:
- Onset within 15–60 minutes (consistent with brief's 20–40 min window)
- Mild, "gentle" visual changes rather than dramatic hallucinations
- Enhanced closed-eye imagery; animation of static objects (plants appearing to move, paintings seeming animated)
- Enhanced tactile perception of textures
- Cognitive clarity maintained throughout
- Warmth, humor, "allowing rather than demanding" character
- **Increased appetite** (distinct from typical LSD appetite suppression)
- Diuretic properties (consistent with brief's "Increased urination" effect)
- Clean aftermath with no reported residual next-day effects
- **Stability concern:** Author reports potency degradation in solution after months of storage even under ideal conditions

### Effect Profile Alignment with Brief

The brief's extensive effects taxonomy aligns well with the class-level serotonergic psychedelic profile established for LSD and related compounds. The specific effects listed — visual drifting, environmental patterning, color alteration, synesthesia, introspection enhancement, pattern recognition enhancement, cognitive euphoria — are all consistent with 5-HT₂A agonist pharmacology (Nichols 2016 [Ref 16]; Carhart-Harris & Friston 2019 [Ref 32]).

The Shulgin account suggests ETH-LAD's visual profile may be somewhat **milder** than LSD at equivalent subjective intensities, with greater emphasis on tactile and cognitive domains than dramatic visual hallucinations.

### Duration

The brief's duration data (total 8–12 hours, peak 4–6 hours, onset 20–40 minutes) is consistent with:
- TiHKAL: 8–12 hours total (Shulgin [Ref 12])
- Coney 2017: modal 8 hours for LSD analogues [Ref 8]
- LSD reference: 6.7–11 hours depending on dose at 25–200 µg (Holze 2021 [Ref 21])

The brief's aftereffects window of 8–48 hours is notably wide; no specific ETH-LAD data could be found to verify or refine this. The Shulgin account suggests a "clean aftermath" with few next-day effects, which argues against the upper end of this range.

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## Safety & Toxicity

### LD50 and Acute Toxicity

**No published LD50 data exist for ETH-LAD.** The brief correctly states that the toxic dose is unknown. No animal acute toxicity studies for ETH-LAD were found in the literature.

For comparison, LSD has an estimated LD50 in rats of approximately 16 mg/kg IV (preclinical data from the 1950s-60s). ETH-LAD's LD50 is unknown, but given its ergoline scaffold and lack of reports of fatal overdose in the literature, it is presumed to have a high therapeutic index by class analogy — though this is **unverified speculation for ETH-LAD specifically**.

### Published Case Reports

**No published case reports of ETH-LAD adverse events or overdose were found.** Searches of PubMed and OpenAlex yielded no clinical case series or individual reports. This is consistent with ETH-LAD's status as a sparse/emerging substance with limited published literature.

### Known Physical Risks

Based on class-level evidence and anecdotal reports:

**Seizure threshold reduction:** The brief lists this as a documented effect. For serotonergic psychedelics including LSD, seizures have been reported, believed to be primarily a risk in genetically predisposed individuals or under conditions of physical stress (dehydration, fatigue, hypoglycemia). No ETH-LAD-specific seizure case reports were found.

**Cardiovascular:** LSD class compounds produce mild increases in heart rate and blood pressure (Holze et al. 2021 [Ref 21]; Liechti 2017 [Ref 22]). Specific cardiovascular data for ETH-LAD are absent.

**Temperature dysregulation:** Listed in the brief and consistent with anecdotal reports suggesting ETH-LAD may produce more pronounced temperature dysregulation than LSD, particularly at higher doses.

**Body load:** Anecdotal community reports describe ETH-LAD as having a higher physical body load than LSD at heavy doses — more pronounced nausea, muscle tension, and general physical discomfort — with an "unpredictable dose-response curve" noted in particular. **This is unverified and based solely on anecdotal sources; no published data confirm or refute this.**

**⚠️ FLAG — Safety-critical:** The brief's dose ranges (Common: 60–150 µg; Strong: 150–225 µg; Heavy: 225+ µg) are considerably higher than Shulgin's described range (40–150 µg, with the strong end being 150 µg) and substantially higher than the common LSD doses used in clinical research (25–200 µg). Combined with anecdotal reports of an unpredictable dose-response curve, the high end of the dose ranges in the brief should be reviewed editorially.

### HPPD

Hallucinogen Persisting Perception Disorder (HPPD) is a risk documented for the class. No ETH-LAD-specific HPPD cases were found. Population survey data suggest HPPD-type symptoms are relatively common (>30%) but rarely distressing in naturalistic psychedelic users; clinically significant Type II HPPD is rare (Zhou et al. 2025; Leistenschneider et al. 2024).

### Psychological Risks

Consistent with class-level evidence:
- Anxiety, panic, and dysphoric reactions particularly at high doses or in vulnerable individuals
- Potential for triggering or exacerbating psychotic episodes in those with predisposition
- Contraindications include: personal or family history of psychosis or schizophrenia; bipolar disorder (class-level, not ETH-LAD-specific)

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## Harm Reduction

### Testing and Identification

Brandt et al. (2017 [Ref 1]) provide the analytical data needed to differentiate ETH-LAD from related compounds:
- GC-MS: Distinctive mass spectral fragmentation pattern
- HPLC: Retention time data
- NMR: Proton NMR characterization
- IR: GC solid-state infrared fingerprint

**Critical for harm reduction:** The 2024 Brandt et al. paper [Ref 3] characterizes EIPLA (N-ethyl-N-isopropyllysergamide) as a structural isomer of ETH-LAD with different mass spectral features. Users and laboratories cannot distinguish ETH-LAD from EIPLA by simple colorimetric tests (e.g., Ehrlich reagent reacts with both); more advanced analytical methods are required.

### Dosing

Shulgin (TiHKAL [Ref 12]) describes doses of 40–150 µg as the active human range. The seed data dose ranges (particularly the "Heavy" threshold at 225+ µg) substantially exceed Shulgin's upper limit and should be flagged. Anecdotal sources suggest ETH-LAD has an unpredictable dose-response curve at higher doses.

**⚠️ FLAG:** The dose ranges in the brief's seed data require editorial review. The "Strong" (150–225 µg) and "Heavy" (225+ µg) categories substantially exceed Shulgin's reported active range and may represent excessive doses given ETH-LAD's reported higher potency vs LSD.

### Stability

Shulgin noted solution instability over months (potency degradation under dark/frozen/anaerobic storage). This has harm reduction implications: stored ETH-LAD solutions may be of uncertain potency.

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## Tolerance & Dependence

### Tolerance Development

**Rapid tolerance onset** is a class feature of serotonergic psychedelics. The mechanism involves 5-HT₂A receptor downregulation in the frontal cortex following repeated activation (de la Fuente Revenga et al. 2022 [Ref 14]). This process is:
- Observable within 24 hours of a single psychedelic dose
- Progressive with repeated dosing over 4 days
- Mediated by 5-HT₂A receptor activation (blocked by M100907)
- Independent of β-arrestin-2 signaling

The brief's tolerance data (builds almost immediately; half-life 6 days; full reset 14 days) is consistent with class-level evidence and standard reporting for LSD-type compounds. No ETH-LAD-specific tolerance data are published.

### Cross-Tolerance

Cross-tolerance between serotonergic psychedelics (e.g., LSD ↔ DOI) is well established (de la Fuente Revenga et al. 2022 [Ref 14]). ETH-LAD would be expected to show complete cross-tolerance with LSD and partial cross-tolerance with psilocybin and other 5-HT₂A agonists. The brief's listing of "psychedelic" as the cross-tolerance class is appropriate.

### Dependence

ETH-LAD is not considered habit-forming (brief states: "not habit-forming"). Nichols (2016 [Ref 16]) notes that classical psychedelics "generally… do not lead to dependence or addiction." The rapid tolerance development itself functionally prevents compulsive use, as repeated doses within days become inactive at the same level.

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## Interactions

### Tramadol (labeled "dangerous" in brief)

Tramadol is a serotonin-norepinephrine reuptake inhibitor (SNRI) with additional opioid agonist properties. Combined with a 5-HT₂A agonist like ETH-LAD, there is theoretical risk of serotonin syndrome through accumulated serotonergic signaling. The "dangerous" designation in the brief is appropriate for a harm reduction context.

**⚠️ FLAG — No published pharmacokinetic or clinical data** on this specific interaction (tramadol + ETH-LAD) were found. The dangerous rating is based on class-level reasoning: tramadol's serotonergic effects combined with ETH-LAD's 5-HT receptor activity could theoretically potentiate serotonergic toxicity. This should be noted as a class-level inference, not an ETH-LAD-specific finding.

### Cannabis (labeled "unknown" in brief)

No published data on the ETH-LAD + cannabis interaction were found. The "unknown" classification is appropriate. Class-level evidence suggests cannabis can unpredictably potentiate psychedelic effects, increase anxiety, and heighten dissociative elements.

### Other Drug Classes (Class-Level, Not ETH-LAD-Specific)

- **MAOIs:** Risk of serotonin syndrome; 5-HT₂A agonist activity combined with monoamine oxidase inhibition can dramatically increase serotonergic load
- **SSRIs/SNRIs:** May blunt psychedelic effects (5-HT₂A receptor downregulation from chronic SSRI use); acute SSRI interaction uncertain
- **Lithium:** Combined use with LSD has been linked to adverse events including seizures; applies by class inference to ETH-LAD

**⚠️ FLAG — All interaction data for ETH-LAD specifically are absent from published literature.** The brief's interaction data (tramadol: dangerous; cannabis: unknown) are consistent with class reasoning but cannot be verified against ETH-LAD-specific sources.

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## Legal Status

### United Kingdom
- **Class A** controlled substance under the Misuse of Drugs Act 1971
- Scheduled via Statutory Instrument 2014 No. 3271 [Ref 18]
- **Effective date: January 7, 2015**
- Controlled alongside: AL-LAD, ALD-52, PRO-LAD, LSZ
- Maximum penalties: life imprisonment for supply; 7 years for possession

### Switzerland
- **Controlled** under Verzeichnis E (List E, Betäubungsmittelgesetz) [Ref 28]
- **Effective date: December 1, 2015**

### Germany
- **Controlled** under the Neue-psychoaktive-Stoffe-Gesetz (NpSG) [Ref 31]
- **Effective date: July 18, 2019**
- Production, import for market placement, administration to another person, and trading are punishable; possession is illegal but not specifically penalized under NpSG

### United States
- **Not explicitly scheduled** under the Controlled Substances Act
- **Federal Analogue Act** (21 U.S.C. § 813) likely applies when intended for human consumption, due to substantial structural and pharmacological similarity to LSD (Schedule I)
- Would be treated as Schedule I substance under Federal Analogue Act in trafficking contexts

### Canada
- **Not a controlled substance** as of 2025 under the Controlled Drugs and Substances Act

### Australia
- No specific scheduling information found for ETH-LAD in available sources
- Likely falls under analogue provisions of the relevant Australian drug legislation (Therapeutic Goods Act); requires editorial verification

### International
- Not scheduled under the 1971 UN Convention on Psychotropic Substances
- Regulation left to national discretion

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## Clinical Trials

**No clinical trials for ETH-LAD have been registered or completed.** ClinicalTrials.gov search returned zero results. ETH-LAD has no clinical research history.

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## Community Feedback Analysis

No community feedback was submitted in Part A2 of the brief. No community feedback items require analysis or investigation.

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## Gaps & Flags

### Critical Gaps (Safety-Relevant)

1. **⚠️ DOSE RANGE FLAG:** The seed data "Strong" (150–225 µg) and "Heavy" (225+ µg) dose categories substantially exceed the upper limits described in TiHKAL by Shulgin (40–150 µg active range, with 150 µg at the strong end). ETH-LAD is reported by multiple sources to be more potent than LSD on a per-microgram basis. Combined with anecdotal reports of an unpredictable dose-response curve, these high dose thresholds require editorial verification before publishing. **No published source confirms these specific values.**

2. **⚠️ RECEPTOR BINDING Ki VALUES UNVERIFIED:** Ki values of 5-HT₂A = 5.1 nM, D1 = 22.1 nM, D2 = 4.4 nM found in a commercial database (MedChemExpress) cannot be traced to a verified primary source. These values should not be used without identifying the underlying publication (likely Hoffman & Nichols 1985 [Ref 9], but full-text access was not possible to confirm).

3. **⚠️ TRAMADOL INTERACTION:** The "dangerous" interaction rating is supported by class-level serotonergic mechanism reasoning but has no published ETH-LAD-specific evidence. Should be labeled as "class-level inference."

4. **⚠️ CANNABIS INTERACTION:** "Unknown" is appropriate; no data found.

5. **⚠️ AFTEREFFECTS DURATION:** The 8–48 hour aftereffects window in the seed data is wide and at odds with Shulgin's description of a "clean aftermath." No published data can verify the upper bound of 48 hours.

### Data Absent from Published Literature

- **No human pharmacokinetic data** for ETH-LAD (plasma half-life, Tmax, bioavailability, AUC); all PK must be inferred from LSD reference
- **No LD50 or acute toxicity data** for any species
- **No published adverse event case reports** for ETH-LAD
- **No controlled dosing studies** in humans
- **No clinical trials** registered or completed
- **No specific ETH-LAD HTR ED50 data** published (unlike AL-LAD, LSZ, ECPLA which have published ED50 values)
- **No Australia-specific legal status data** found

### Areas Relying on Structural Analogy / Class Inference

The following sections of this report rely on LSD class-level evidence rather than ETH-LAD-specific data:
- Pharmacokinetics (half-life, elimination kinetics)
- Cardiovascular effects (heart rate, blood pressure increases)
- Serotonin syndrome risk with MAOIs/SSRIs/tramadol
- HPPD risk
- Seizure risk
- Psychological contraindications (history of psychosis)
- Tolerance mechanism (5-HT₂A downregulation)

All such claims should be qualified as "by class analogy" in the generated article.

### Contradictions Between Sources

- **Dose ranges:** Shulgin TiHKAL (40–150 µg active, [Ref 12]) vs brief seed data (Common 60–150 µg, Strong 150–225 µg, Heavy 225+ µg). Not necessarily contradictory (Shulgin's account is exploratory, not a comprehensive dose study), but the strong/heavy thresholds need external validation.
- No other direct contradictions between sources were identified.

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*Research completed: 2026-04-26. Total citations in registry: 32. Clinical trials searched: 0 results. No community feedback to adjudicate.*