Depressants, Sedatives & Related Agents
Comprehensive Substance Reference & Harm Reduction Guide
Depressants, Sedatives & Related Agents
GUIDE-WIDE SAFETY NOTICE: This guide is for recognition, harm-reduction, and emergency-reference purposes. Appearance alone cannot reliably identify a substance. Counterfeit pills, powders, vapes, edibles, and street mixtures may contain unexpected drugs. Do not taste, smell closely, burn, or handle an unknown substance to identify it. If poisoning is possible, contact Poison Control (U.S. 1-800-222-1222) or 911 for severe symptoms.
3. Depressants, Sedatives & Related Agents
| Substance | Appearance, Route & Intoxication | Physical Side Effects | Severe Toxicity / Overdose & Response |
| Benzodiazepines (Xanax, Valium) | Prescription tablets / bars. Usually oral. Slurred speech, poor coordination, confusion, relaxation. | Drowsiness, dizziness, muscle weakness, poor coordination, slowed reflexes, blurred vision. | Overdose: Deep unconsciousness, dangerous breathing depression (worse with opioids/alcohol), aspiration risk. Response: 911 for severe sedation/abnormal breathing. Recovery position. Naloxone if opioid co-exposure. |
| Alcohol | Beer, wine, spirits. Oral. Slurred speech, poor balance, impaired judgment. | Flushing, nausea/vomiting, dehydration, headache, poor coordination, impaired temperature regulation. | Overdose: Unconsciousness, slow/irregular breathing, repeated vomiting, blue/pale skin, seizures. Response: 911 for unconsciousness/abnormal breathing. Recovery position, keep warm. |
| GHB / GBL | Clear, colorless liquid or powder. Usually swallowed. Euphoria, disinhibition, rapidly increasing drowsiness. | Drowsiness, dizziness, nausea/vomiting, sweating, slowed heart rate/breathing, reduced muscle tone. | Overdose: Sudden coma, severe respiratory depression, seizures, slow heart rate. Response: 911, airway monitoring, recovery position. Do not leave alone. |
| Xylazine ("Tranq") | White/brown powder mixed with illicit opioids. Snorted, smoked, injected. Profound sedation, slow breathing. | Profound sedation, slowed breathing, low BP, slow heart rate; repeated exposure causes severe skin wounds/ulcers. | Overdose: Severe CNS depression, low BP, prolonged sedation. Response: 911, breathing support. Give naloxone for opioid component (naloxone does not reverse xylazine). |
| Barbiturates | Prescription/veterinary tablets/capsules. Oral or injected. Drowsiness, slurred speech, confusion. | Drowsiness, dizziness, poor coordination, slowed breathing, low BP, nausea, weakness. | Overdose: Coma, low BP, severe respiratory depression, hypothermia. Response: 911, airway/breathing support, recovery position. |
| Z-drugs (Zolpidem / Ambien) | Prescription tablets. Oral. Marked sleepiness, confusion, unusual behavior or amnesia. | Drowsiness, dizziness, headache, impaired coordination, nausea, unusual sleep behaviors. | Overdose: Profound sedation, falls/injury, breathing depression with alcohol/opioids. Response: 911 for unresponsiveness/abno rmal breathing. Recovery position. |
| Gabapentin / Pregabalin | Prescription capsules/tablets/liquid. Oral. Dizziness, sleepiness, poor coordination, blurred vision. | Dizziness, sleepiness, blurred vision, swelling of hands/feet, weight gain; breathing risk rises with opioids. | Overdose: Severe sedation or respiratory depression with CNS depressants. Response: Call 911 for abnormal breathing or severe sedation. |
| Muscle Relaxants (Baclofen, Cyclobenzaprine) | Prescription tablets/capsules. Oral. Drowsiness, dizziness, weakness, confusion. | Drowsiness, weakness, dry mouth, blurred vision, nausea, low BP, abnormal heart rhythm. | Overdose: Coma, respiratory depression, arrhythmia, seizure, severe weakness. Response: Contact Poison Control for excess dose; 911 for severe symptoms/seizures. |
| Clonidine | Tablets or transdermal patches. Oral/transdermal. Sleepiness, dizziness, slow heart rate, low BP. | Sleepiness, dry mouth, dizziness, slow heart rate, low BP, constipation. | Overdose: Marked bradycardia, hypotension, pinpoint pupils, severe sedation, breathing depression. Response: Call Poison Control promptly; 911 for severe symptoms. |
| Phenibut | White powder or capsules. Oral. Sedation, dizziness, impaired coordination, paradoxical agitation. | Drowsiness, dizziness, nausea, poor coordination; heavy use leads to dependence and severe withdrawal. | Overdose: Severe sedation, delirium, breathing depression. Response: Poison Control for exposure; 911 for severe agitation, seizures, or unresponsiveness. |