How drugs enter your body - and why the same substance can be dramatically more dangerous depending on how it's taken.
Faster onset = more intense rush = shorter duration = higher addiction potential = higher overdose risk. This isn't a moral judgment - it's pharmacokinetics.
PO, ingestion, eating, parachuting
Stomach/intestine → hepatic portal vein → liver (processes some of the drug) → systemic circulation → brain
• Nausea/vomiting
• Slow unpredictable onset → impatient redosing → accidental overdose
• Food in stomach changes absorption
• GI irritation/ulceration
• Liver strain
• Tooth enamel erosion
Under the tongue, against the cheek
Oral mucosa → bloodstream (skips liver entirely)
• Extremely bitter taste
• Local numbness/irritation
• Swallowing saliva redirects dose to oral route
• Oral mucosa erosion with repeated use
• Dental issues
Common for LSD (blotter), buprenorphine (Suboxone), some benzos.
Intranasal, sniffing, railing, bumping
Nasal mucous membrane → bloodstream → brain. Part of dose drips to stomach (oral absorption).
• Nosebleeds
• Burning/congestion
• Post-nasal drip (nausea, bad taste)
• Sharing straws/notes transmits Hepatitis C via microscopic blood
• Chronic sinusitis
• Loss of smell (anosmia)
• Nasal septum perforation
• Saddle nose deformity
• Palatal perforation (rare, primarily cocaine)
Vasoconstrictive substances restrict blood flow → oxygen starvation → tissue death → perforation.
Boofing, plugging, booty bumping
Rectal mucosa → bloodstream. Lower ⅔ skips the liver; upper ⅓ gets processed by liver first.
• Rectal mucosal irritation/damage
• Difficulty controlling dose
• Overdose risk from high bioavailability
• Chronic mucosal inflammation
• Increased STI/HIV risk (tears create entry points)
Legitimate medical route - suppositories used for anti-nausea meds, seizure medication, pain relief.
Vaping, freebasing
Heated below combustion → vapor → lungs (70m² surface, 0.5μm barrier) → pulmonary veins → brain
• Burns (improvised devices)
• Chest tightness
• Very fast onset → intense rush → strongest redosing drive
• Chronic respiratory irritation
• Reduced lung capacity
• Unknown long-term for newer devices
Produces drug effect with dramatically fewer toxic byproducts than combustion. Harm reduction orgs recommend vaporizing over smoking.
Combustion, chasing (heating on foil)
Same lung absorption as vaporizing, BUT combustion adds tar, carbon monoxide, and carcinogens
• All vaporizing risks PLUS toxic combustion byproducts
• Burns from foil/pipes
• Cancer risk (from combustion, not the drugs)
• Chronic bronchitis
• Crack lung (smoked cocaine)
• All vaporizing long-term risks
Route transitioning from injection to smoking is an established harm reduction strategy.
Patches, topical absorption
Drug in adhesive matrix → absorbed through skin → capillaries in dermis → systemic circulation
• Skin irritation
• Slow onset (low abuse potential as designed)
• Contact dermatitis at application sites
DANGER: Heat dramatically accelerates fentanyl patch absorption → overdose deaths. Cutting patches causes dose dumping. Used patches still contain significant residual drug.
Muscle shot, IM
Injected into muscle tissue → absorbed through capillary beds → systemic circulation → brain
• Injection site pain/swelling
• Abscess if technique is poor
• Nerve damage (incorrect site)
• Muscle fibrosis/scarring with repeated use
• Bloodborne infections from shared equipment
• Sterile abscesses
Common medical route (vaccines, ketamine clinics). Slower onset than IV reduces overdose risk but also reduces ability to titrate dose. Same sterile equipment rules apply - syringe service programs provide supplies.
Shooting, slamming, mainlining, fixing
Dissolved in liquid → injected into vein → immediate systemic circulation → brain in ~15–30 seconds
• Overdose (entire dose hits at once - no buffer)
• Arterial injection (medical emergency)
• Air embolism
• Injection site infections/abscesses
• Vein collapse/sclerosis
• Bloodborne infections: HIV, Hepatitis B, Hepatitis C
• Endocarditis (heart valve infection)
• Sepsis
• Strongest conditioning loop for dependence
Syringe service programs provide sterile equipment. Never Use Alone (1-800-484-3731) - stays on the line during use.
When you swallow a drug, it travels through the digestive system to the liver before reaching your brain. The liver breaks down a fraction of the drug before it ever arrives - pharmacologists call this "first-pass metabolism." Routes that skip the liver (snorting, smoking, injection, sublingual, rectal) deliver more of the dose to your brain. This is why the same amount of a drug can be much more potent through a non-oral route.
The percentage of a dose that reaches your bloodstream in active form. IV injection = 100% by definition. Everything else is less. Why this matters: if you switch routes without adjusting your dose, you can accidentally give yourself a much larger effective dose. Route-switching without dose adjustment is a common cause of overdose death.