Health literacy

Learn about your health

Plain-English guides to how drugs work, what addiction really is, how the FDA operates, and how to advocate for yourself.

Browse by topic

What do you want to understand?

💊
How drugs work

From absorption to elimination — how pills actually work in your body, explained without the jargon.

8 guides · Beginner to advanced
🧠
Addiction & dependency

What addiction really is neurologically, why willpower alone isn’t the answer, and what evidence-based treatment looks like.

6 guides · No judgment, just science
🏛️
The FDA & drug approval

How drugs get approved, what clinical trial phases mean, and how to read a drug label.

5 guides · Know your rights
⚠️
Drug safety & interactions

Which drug combinations are dangerous, and what questions to ask your pharmacist.

7 guides · Practical and actionable
💙
Mental health medications

Antidepressants, antipsychotics, mood stabilizers — what they do, what to expect, and common misconceptions.

9 guides · SSRIs to antipsychotics
📢
Advocating for yourself

How to talk to your doctor about side effects, how to report an adverse event to the FDA, and how to get help when insurance says no.

4 guides · Patient empowerment
How drugs work

From pill to effect: what actually happens in your body

Every drug goes on a journey — absorbed through your gut, distributed through your blood, metabolized in your liver, and eventually excreted. Understanding this helps you understand why drugs work, why they cause side effects, and why timing matters.

Read full guide →
When you swallow a pill, it dissolves in your stomach and the active ingredient passes through the gut wall into your bloodstream. Different formulations (tablets, capsules, extended-release) control how fast this happens.
Your liver is the body’s chemical processing plant. Most drugs are metabolized by CYP450 enzymes there. This is why grapefruit juice affects some drugs — it blocks a key enzyme — and why some drug interactions happen: they compete for the same metabolic pathway.
Half-life is the time it takes your body to reduce the drug’s blood concentration by half. A drug with a short half-life (like Xanax at 6-12 hours) requires more frequent dosing and causes stronger withdrawal. Long half-life (like Valium at 20-100 hours) stays in the system longer — useful for tapering.
Most drugs work by binding to specific receptors. The problem: those receptors exist in multiple locations. An SSRI targets serotonin receptors in the brain — but serotonin receptors also exist in the gut (causing nausea) and in the genitals (causing sexual dysfunction). Side effects are usually the drug doing its intended thing in the wrong place.
Addictive drugs flood the brain’s reward circuit (nucleus accumbens) with dopamine — much more than natural rewards. The brain compensates by downregulating its own dopamine system. This is why people with addiction need the drug just to feel normal, and why withdrawal is so difficult.
By the numbers

Drug dependency & misuse in America

Public data from SAMHSA, NIH, and CDC — surfaced so awareness can drive action.

Annual substance use disorder prevalence
Adults 18+ with past-year SUD (SAMHSA 2023)
Alcohol
28.9M
Cannabis
16.3M
Opioids
6.1M
Stimulants
3.7M
Benzodiazepines
2.4M
Treatment access gap (2023)
Of 48.7M who needed treatment (SAMHSA)
93%
did not receive
specialty treatment
Of 48.7M Americans who needed substance use treatment, only 3.4M (7%) received it at a specialty facility. The gap is cost, stigma, and access.
SAMHSA helpline: 1-800-662-4357 · Free · 24/7
Medical glossary

Words your doctor uses, explained

Contraindicated
Should not be used — the combination with another drug or condition could cause serious harm.
Half-life
The time it takes the body to reduce a drug’s blood concentration by half.
Titration
Gradually adjusting a drug dose over time to find the optimal level or safely discontinue.
Bioavailability
The fraction of a drug that actually reaches the bloodstream. Oral drugs often have lower bioavailability than injected ones.
Black box warning
The FDA’s strongest warning — placed on labels when there is evidence of serious or life-threatening risk.
Schedule II drug
A drug with high potential for abuse and dependence. Includes oxycodone, Adderall, and fentanyl.
Adverse event
Any harmful or unintended response to a drug. Can be reported to the FDA’s MedWatch system.
CYP450 enzymes
A family of liver enzymes that metabolize most drugs. Inhibiting or inducing these causes many drug interactions.
PAWS
Post-Acute Withdrawal Syndrome — prolonged withdrawal lasting weeks to months after acute withdrawal ends.
Tolerance
The body’s adaptation requiring more drug for the same effect. Develops with opioids, benzos, stimulants, and alcohol.
Receptor agonist
A drug that activates a receptor to produce a biological response — mimicking a natural molecule like dopamine.
Receptor antagonist
A drug that blocks a receptor, preventing natural molecules from binding and producing their usual effect.