Flakka is the street name for α-pyrrolidinovalerophenone (α-PVP), a potent second-generation synthetic cathinone ("bath salt") that acts as a dopamine and norepinephrine transporter reuptake inhibitor (with negligible serotonin transporter activity), producing a severe sympathomimetic toxidrome. [1] It functions as a more effective reinforcer than cocaine or methamphetamine in animal models, conferring extremely high abuse liability. [2] Toxicity is managed with aggressive sedation, cooling, and supportive care — there is no specific antidote. [3-4]
1. History
- Route of administration: Smoked/vaporized (most common), insufflated (snorted), injected IV, ingested orally, or administered rectally [6-7]
- Timing: Subjective effects peak ~40 minutes after intranasal use and last 3–5 hours; onset is faster with smoking/IV [8]
- Dose: Potent at doses as low as 5–10 mg [9]
- Key HPI questions:
- What substance was used, how much, and by what route?
- Time of last use?
- Co-ingestions (polydrug use is the rule — synthetic cannabinoids, ketamine, GHB, opioids, alcohol are common) [10-11]
- Prior episodes of use or intoxication?
- Suicidal ideation or self-injurious behavior?
- Important negatives: Deny trauma, ingestion of other pills, access to medications, recent illness/fever
2. Alarm Features
- Hyperthermia >40°C (104°F) — rapidly life-threatening and the leading cause of death [3][12]
- Refractory agitation/excited delirium with risk of sudden cardiac arrest
- Seizures or status epilepticus [12]
- Cardiac arrest (VF, VT, PEA) [3-4]
- Severe metabolic acidosis (pH <7.0 in fatal cases) [12]
- Rhabdomyolysis with acute kidney injury
- Multiorgan failure — rapid progression in severe cases [12]
- Chest pain suggesting coronary vasospasm or takotsubo cardiomyopathy [3][13]
3. Medications
First-line treatment
- Benzodiazepines (midazolam IM/IV, lorazepam, diazepam) — cornerstone of management for agitation, seizures, and hyperadrenergic state. Large doses may be required [3][14-15]
- Antipsychotics (haloperidol, droperidol, olanzapine) — adjunctive for agitation/psychosis [3][16]
Adjunctive/refractory
- Dexmedetomidine — useful for refractory agitation and can also treat hypertension/tachycardia [14]
- Propofol or phenobarbital — for refractory agitation requiring deeper sedation [14]
For persistent hypertension after adequate sedation
- Calcium channel blockers (nicardipine, clevidipine), phentolamine, or nitroglycerin (if ischemia) [3][14]
- Avoid long-acting antihypertensives — risk of hemodynamic collapse as drug wears off [14]
Contraindicated/caution
- Pure beta-blockers are generally contraindicated (risk of unopposed alpha stimulation) [14]
- If a beta-blocker is needed, use one with alpha-1 antagonism (e.g., labetalol, carvedilol) [14]
- Sustained physical restraints without sedation are associated with death [3]
4. Diet
- Not directly applicable in the acute setting
- Aggressive IV fluid resuscitation is critical to maintain renal perfusion and treat rhabdomyolysis [15]
- Avoid oral intake until mental status normalizes and aspiration risk is mitigated
5. Review of Systems
- Neuro/Psych: Agitation, hallucinations (visual/auditory), paranoia, delirium, aggression, self-injurious behavior, suicidal ideation, seizures [7][9-10]
- Cardiovascular: Chest pain, palpitations
- Musculoskeletal: Muscle rigidity, myalgias (rhabdomyolysis)
- GU: Decreased urine output (AKI from rhabdomyolysis)
- Constitutional: Diaphoresis, hyperthermia
- GI: Nausea, vomiting
6. Collateral History and Family History
- Collateral from EMS, bystanders, or friends is essential — patients are often unable to provide history
- Determine substance identity if possible (packaging, paraphernalia, text messages)
- Polydrug use is extremely common: 85.6% of flakka users also used synthetic cannabinoids, 72.3% ketamine, 59.1% marijuana [11]
- Psychiatric history, prior substance use disorder, and prior ED visits for intoxication
- Family history of cardiac disease or sudden death may influence risk stratification
7. Risk Factors
- Young males (median age 27–32, ~79% male in case series) [6][10]
- Prior psychostimulant use history [8]
- Polydrug use (the norm, not the exception) [9][11]
- Lower socioeconomic status and lower parental education level [11]
- Availability via internet and low cost [7][9]
- Motivations include libido enhancement, appetite suppression, and euphoria [9]
- Chemsex context [17]
8. Differential Diagnosis
- Other sympathomimetic toxidromes: Methamphetamine, cocaine, MDMA, PCP — clinically indistinguishable; treatment is the same [4]
- Anticholinergic toxidrome: Dry skin, urinary retention, absent bowel sounds (vs. diaphoresis in sympathomimetics)
- Serotonin syndrome: Clonus, hyperreflexia, diarrhea — more prominent with serotonergic agents (α-PVP has minimal serotonin activity)
- Neuroleptic malignant syndrome: Slower onset, lead-pipe rigidity, recent antipsychotic use
- Thyroid storm: History of thyroid disease, goiter
- Meningitis/encephalitis: Fever + altered mental status — consider LP if infection cannot be excluded
- Excited delirium from any cause
- Primary psychiatric emergency (mania, acute psychosis) — a positive drug test does not exclude concurrent medical emergency [14]
9. Past Medical History
- Prior substance use disorder or overdose episodes
- Psychiatric diagnoses (bipolar disorder, schizophrenia)
- Cardiac disease (increases risk of MI from vasospasm)
- Renal disease (lower threshold for AKI)
- Seizure disorder
- HIV/hepatitis status (higher prevalence in stimulant users) [14]
10. Physical Exam
Vital signs
- Tachycardia (80% of cases) [10]
- Hypertension (33%) [10]
- Hyperthermia — obtain core (rectal) temperature; peripheral may underestimate [3]
Focused exam
- Neuro: Agitation, delirium, mydriasis, hyperreflexia, tremor, clonus, seizures [7]
- Skin: Diaphoresis (distinguishes from anticholinergic), skin breakdown from self-injury
- CV: Tachycardia, murmurs (endocarditis if IV use)
- MSK: Muscle rigidity, tenderness (rhabdomyolysis)
- Trauma survey: Self-inflicted injuries, restraint injuries, occult head trauma
11. Lab Studies
Recommended labs per ASAM/AAAP guidelines: [14]
- CBC, CMP (renal function, electrolytes, glucose)
- CK/CPK — elevated in 75% of cases (rhabdomyolysis marker) [6]
- Lactate — elevated in >70% [6]
- Troponin — rule out myocardial injury
- Coagulation studies — coagulopathy in ~67% [6]
- VBG/ABG — acid-base disorder in 63% [6]
- Urinalysis — myoglobinuria
- Urine drug screen — standard immunoassays will NOT detect α-PVP; mass spectrometry (LC-MS/MS) is required for confirmation [7][14]
- Hepatic function panel
- Consider HIV, hepatitis B/C, STI screening in appropriate patients [14]
12. Imaging
- CT head without contrast: If altered mental status, seizures, focal neurological deficits, or trauma suspected
- Chest X-ray: If respiratory distress, aspiration concern, or hypoxia
- CT angiography: If concern for aortic dissection (severe hypertension + chest/back pain)
- Imaging is not routinely necessary in straightforward sympathomimetic toxidrome with improving clinical trajectory
13. Special Tests
- Poisoning Severity Score (PSS): Can be used retrospectively to grade severity (60% moderate, 17% severe in one series) [10]
- Point-of-care ultrasound: Assess cardiac function if hemodynamically unstable (evaluate for takotsubo cardiomyopathy) [3]
- Confirmatory toxicology: LC-MS/MS on blood and urine — α-PVP itself and metabolites (β-hydroxy-α-PVP, α-PVP lactam) are targets [7]
- Continuous core temperature monitoring in severe cases
14. ECG
- Sinus tachycardia — most common finding [10]
- ST-segment changes — may indicate coronary vasospasm or demand ischemia [3][13]
- QTc prolongation — reported with some synthetic cathinones
- Ventricular tachycardia/ventricular fibrillation — in severe/fatal cases [3][12]
- Brugada-like pattern — reported with some cathinones
- Continuous cardiac monitoring is recommended for all symptomatic patients [18]
15. Assessment
α-PVP toxicity presents as a severe sympathomimetic toxidrome with a spectrum of severity: [4][10]
- Mild: Tachycardia, agitation, mild hypertension — resolves with observation and low-dose benzodiazepines
- Moderate (60% of cases): Persistent sympathomimetic findings, elevated CK, metabolic acidosis, coagulopathy [10]
- Severe (17%): Hyperthermia >40°C, seizures, refractory agitation, rhabdomyolysis, cardiac dysrhythmias [10]
- Fatal (5%): Refractory VT/VF, multiorgan failure, cerebral edema [10][12]
Key distinguishing features: Neuropsychiatric symptoms (hallucinations, paranoia, aggression) are transient and often resolve before ED arrival, while sympathomimetic physical findings (tachycardia, elevated CK, acidosis) are more persistent. [6]
16. Treatment Plan
Initial stabilization (ABCs)
- Secure airway if GCS depressed or unable to protect
- IV access, continuous monitoring (cardiac, SpO2, core temperature)
Agitation — the treatment priority
- Benzodiazepines first-line: Midazolam 5–10 mg IM/IV, repeat q5 min PRN; or lorazepam 2–4 mg IV [3][14]
- Antipsychotics adjunctive: Haloperidol 5–10 mg IM or droperidol 2.5–5 mg IM/IV; olanzapine 10 mg IM [3][16]
- Dexmedetomidine infusion for refractory cases [14]
- Propofol or phenobarbital if above measures fail [14]
- Minimize physical restraint duration — associated with death if used without effective sedation [3]
Hyperthermia (>40°C)
- Aggressive external cooling — ice water immersion is fastest and preferred; evaporative cooling is an alternative [3]
- Target cooling rate >0.15°C/min, which is associated with improved survival [3]
- Cooling blankets and cold packs are inferior [3]
- Dantrolene — conflicting evidence; not routinely recommended [3]
Cardiovascular
- Adequate sedation usually controls hypertension and tachycardia [4]
- Persistent hypertension: Nicardipine, clevidipine, phentolamine, or nitrates [3][14]
- Coronary vasospasm: Nitroglycerin, calcium channel blockers [3]
- Takotsubo cardiomyopathy with cardiogenic shock: Consider VA-ECMO or intra-aortic balloon pump — often resolves in days to weeks [3]
- Cardiac arrest: Standard ACLS; consider ECLS [3]
Rhabdomyolysis
Seizures
17. Disposition
Admit/ICU criteria
- Hyperthermia >40°C
- Seizures
- Cardiac dysrhythmias or ischemia
- Severe metabolic acidosis
- Rhabdomyolysis with CK >5,000 or rising, or AKI
- Refractory agitation requiring continuous sedation
- Intubated patients
Observation (6–8 hours minimum)
- Moderate sympathomimetic findings responding to benzodiazepines
- Trending labs (CK, renal function, lactate)
Discharge criteria
- Asymptomatic with normal vital signs for ≥4–6 hours
- Normal mental status
- Tolerating PO
- CK trending down, normal renal function
- Safe disposition (no suicidal ideation, safe environment)
Consult triggers
- Toxicology/Poison Control — early for any severe presentation
- Cardiology — if ischemia, dysrhythmias, or suspected takotsubo
- Nephrology — if AKI or severe rhabdomyolysis
- Psychiatry — for suicidal ideation, psychosis, or substance use disorder evaluation
18. Follow Up / Return Precautions
- Follow-up: PCP or addiction medicine within 48–72 hours; psychiatry if psychotic symptoms persist
- Substance use disorder referral: ASAM/AAAP guidelines recommend connecting patients to treatment [14]
- Return precautions: Return immediately for chest pain, recurrent confusion/agitation, decreased urine output, dark urine, fever, seizures, or suicidal thoughts
- Expected course: Neuropsychiatric symptoms typically resolve within hours; physical findings (elevated CK, acidosis) may persist 24–48 hours [6]
- Counseling: α-PVP is more reinforcing than cocaine or methamphetamine — high relapse risk; standard drug screens will not detect it [2][7]
References
1. DARK Classics in Chemical Neuroscience: Α-Pyrrolidinovalerophenone ("Flakka"). — Kolesnikova TO, Khatsko SL, Demin KA, Shevyrin VA, Kalueff AV. ACS Chemical Neuroscience. 2019.
2. Self-Administration of the Synthetic Cathinones 3,4-Methylenedioxypyrovalerone (MDPV) and Α-Pyrrolidinopentiophenone (Α-Pvp) in Rhesus Monkeys. — Collins GT, Sulima A, Rice KC, France CP. Psychopharmacology. 2019.
3. Part 10: Adult and Pediatric Special Circumstances of Resuscitation: 2025 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. — Cao D, Arens AM, Chow SL, et al. Circulation. 2025.
4. 2023 American Heart Association Focused Update on the Management of Patients With Cardiac Arrest or Life-Threatening Toxicity Due to Poisoning: An Update to the American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. — Lavonas EJ, Akpunonu PD, Arens AM, et al. Circulation. 2023.
5. Case 40-2013. — Benzer TI, Nejad SH, Flood JG. The New England Journal of Medicine. 2013.
6. Clinical Characteristics of Α-Pyrrolidinovalerophenone (Α-Pvp) Poisoning. — Umebachi R, Aoki H, Sugita M, et al. Clinical Toxicology. 2016.
7. The Synthetic Cathinone Α-Pyrrolidinovalerophenone (Α-Pvp): Pharmacokinetic and Pharmacodynamic Clinical and Forensic Aspects. — Nóbrega L, Dinis-Oliveira RJ. Drug Metabolism Reviews. 2018.
8. Acute Pharmacological Effects of Α-PVP in Humans: A Naturalistic Observational Study. — De la Rosa G, Papaseit E, Hladun O, et al. Frontiers in Pharmacology. 2025.
9. Synthetic Cathinones in Belgium: A Cluster of Poly-Drug Intoxications Involving Α-Pyrrolidinoisohexiophenone (Α-PiHP). — Balcaen M, De Brabanter N, Verougstraete N, et al. Clinical Toxicology. 2025.
10. Toxicity Evaluation of Α-Pyrrolidinovalerophenone (Α-Pvp): Results From Intoxication Cases Within the STRIDA Project. — Beck O, Franzén L, Bäckberg M, Signell P, Helander A. Clinical Toxicology. 2016.
11. "Flakka" Use Among High School Seniors in the United States. — Palamar JJ, Rutherford C, Keyes KM. Drug and Alcohol Dependence. 2019.
12. Fatal Polydrug Intoxication Involving Synthetic Cathinones in Taiwan: A Case Series and Emergency Management Implications. — Cheng HC, Wang TY, Chang CM, Liao PH, Chen YC. The Journal of Emergency Medicine. 2026.
13. Synthetic Cannabinoids and Cathinones Cardiotoxicity: Facts and Perspectives. — Radaelli D, Manfredi A, Zanon M, et al. Current Neuropharmacology. 2021.
14. The ASAM/AAAP Clinical Practice Guideline on the Management of Stimulant Use Disorder. — Journal of Addiction Medicine. 2024.
15. Synthetic Cathinones ("Bath Salts"). — Banks ML, Worst TJ, Rusyniak DE, Sprague JE. The Journal of Emergency Medicine. 2014.
16. Treatment of Toxicity From Amphetamines, Related Derivatives, and Analogues: A Systematic Clinical Review. — Richards JR, Albertson TE, Derlet RW, et al. Drug and Alcohol Dependence. 2015.
17. Clinical Manifestations and Analytical Reports for MDPHP Acute Intoxication Cases. — Arillotta D, Totti A, Dimitrova A, et al. Journal of Pharmaceutical and Biomedical Analysis. 2024.
18. Update to Practice Standards for Electrocardiographic Monitoring in Hospital Settings: A Scientific Statement From the American Heart Association. — Sandau KE, Funk M, Auerbach A, et al. Circulation. 2017.