United States – October 27, 2026 -- Cannabis sold in legal-sale states in 2023 contains 25-90% THC, compared with roughly 2-4% before 1990, so parents who tried it in their youth may be thinking of a very different drug. Mothers Against Drunk Driving (MADD) is urging parents to update their conversations with teens through its Power of Parents program.
Potency has jumped by more than 100 times
MADD says the difference can be over 100-fold. Its comparison: if beer had strengthened the same way, one beer today would equal more than 20 beers in 1990. Beer potency, by contrast, has changed very little because of strong regulation.
THC hits a brain that is still developing
THC alters communication inside the brain and between brain and body. It affects movement, coordination, sensation, judgment, decision-making, memory and mood. Frequent use is linked to slower reaction time, learning and memory problems, anxiety, depression, and lung irritation from smoking or vaping.
Because brains develop into the mid-20s, adolescent use can alter pathways for decision-making, impulse control and emotional regulation.
Driving and mixing substances raise the stakes
Cannabis affects judgment, attention and reaction time. MADD suggests teens check a potential driver with three senses: sight (glassy or bloodshot eyes, unsteady gait), sound (slurred or unusually fast speech) and smell (alcohol or cannabis odors). Teens should call for help rather than ride with an impaired driver.
When alcohol and cannabis are combined, substances compound rather than cancel each other out. Medications also carry risk. Prescription and over-the-counter drugs can be misused to get high, stay awake, lose weight or “perform.” MADD recommends locking drug cabinets, tracking quantities and disposing of leftovers.
Parents can answer “Did you use?” honestly without dwelling on the past
If a teen asks, MADD advises parents to be honest without centering their own history, to mention that today's cannabis is much stronger, and to turn to the present. Its sample line: “If I could go back and do things differently, I would.”
A family plan puts the rules in writing
MADD's suggested agreements: no use under 21, which is illegal in every state; no impaired driving; never ride with someone who has used; and call for help at any time, with questions saved for later and consequences as agreed. Families should also practice a “tap-out” text and settle on a consistent pickup spot.