Types of medications · Sophrosyne Mental Health

How do medications work?

Nerve cells in the brain communicate using chemical messengers called neurotransmitters, such as dopamine and serotonin. Psychiatric medications work by changing how much of a neurotransmitter is available, or how cells respond to it. That is part of why they often take time to work, and why taking them consistently matters.

Antidepressants

Antidepressants treat depression and several anxiety-related disorders. They are grouped into classes by which neurotransmitters they mainly affect. Most people take some time — often several weeks — to feel the full benefit, which is normal, and for many people antidepressants work best alongside therapy.

A safety note for all antidepressants

Antidepressants carry an FDA “boxed warning” — the FDA’s most prominent warning — about a small increased risk of new or worsening suicidal thoughts or behavior in children, teenagers, and young adults under 25, especially in the first few weeks of treatment or when a dose changes.

The balanced picture, because context matters:

Depression and anxiety themselves carry a risk of suicidal thinking. For many young people, treating the illness lowers that risk overall. The warning exists so everyone pays close attention during the early window — not because the medication is unsafe to use.
The guidance is to be monitored closely, especially early and after any dose change. Tell someone you trust and your prescriber about new or worse restlessness, agitation, trouble sleeping, or thoughts of self-harm.
Do not stop an antidepressant on your own. If anything feels wrong, that is a reason to contact your prescriber quickly, not to quit suddenly.

SSRIs (selective serotonin reuptake inhibitors)

What they treat: a common first-line treatment for depression, and for several anxiety disorders — generalized anxiety, panic, social anxiety, OCD, and PTSD.
Examples: fluoxetine (Prozac), sertraline (Zoloft), escitalopram (Lexapro), citalopram (Celexa), paroxetine (Paxil).
How they work: increase the serotonin available between nerve cells by blocking its reuptake.
Common side effects: nausea, headache, sleep changes, dry mouth, restlessness, dizziness, and sexual or appetite changes; these often ease over a few weeks.
Key safety: the antidepressant boxed warning above; taper rather than stop suddenly.

SNRIs (serotonin and norepinephrine reuptake inhibitors)

What they treat: depression and generalized and other anxiety disorders; some are also used for certain chronic-pain conditions.
Examples: venlafaxine (Effexor XR), duloxetine (Cymbalta), desvenlafaxine (Pristiq), levomilnacipran (Fetzima).
How they work: increase both serotonin and norepinephrine by blocking their reuptake.
Common side effects: nausea, dry mouth, dizziness, headache, sweating, tiredness, constipation, and sleep or sexual changes; some can raise blood pressure.
Key safety: the antidepressant boxed warning above; tapered, not stopped suddenly.

TCAs (tricyclic antidepressants)

What they treat: an older class, usually tried after SSRIs and SNRIs — depression (often when other medicines haven’t worked), OCD (for example clomipramine), and some are used for chronic pain.
Examples: amitriptyline, nortriptyline, imipramine, clomipramine.
How they work: increase serotonin and norepinephrine, and also act on other receptors, which is why they tend to cause more side effects.
Common side effects: dry mouth, constipation, blurred vision, dizziness on standing, drowsiness, weight changes, and effects on heart rhythm.
Key safety: the antidepressant boxed warning above; because they affect heart rhythm, a prescriber reviews heart health and usually tries newer antidepressants first.

NaSSAs (noradrenergic and specific serotonergic antidepressants)

What they treat: depression, sometimes anxiety, and an option for people who cannot take SSRIs.
Examples: mirtazapine (Remeron).
How they work: increase norepinephrine and serotonin signaling by acting on particular receptors.
Common side effects: drowsiness (strongest at first), increased appetite and weight gain, dry mouth, dizziness; fewer sexual side effects than SSRIs.
Key safety: the antidepressant boxed warning above.

Mood stabilizers

Mood stabilizers mainly treat bipolar disorder, evening out mania and depression. Some are also added to an antidepressant when depression has been hard to treat.

Lithium

What it treats: bipolar disorder (manic episodes and relapse prevention); sometimes added to an antidepressant in hard-to-treat depression; in some people it may reduce suicide risk.
How it works: reduces abnormal brain activity; the full mechanism is still being studied.
Common side effects: nausea, hand tremor, increased thirst and urination, weight gain, and tiredness.
Key safety: lithium has a narrow safe range, so it needs regular blood tests for lithium levels, plus thyroid and kidney monitoring. Dehydration, some pain relievers (NSAIDs), and some blood-pressure medicines can push levels too high. Signs of toxicity — vomiting, diarrhea, severe tremor, slurred speech, loss of coordination — need urgent medical care.

Anticonvulsant mood stabilizers

Some anti-seizure medicines also stabilize mood in bipolar disorder. They are not interchangeable — their key risks differ:

Examples: lamotrigine, valproate (valproic acid / divalproex), carbamazepine.
Lamotrigine: carries an FDA boxed warning for serious, rarely life-threatening skin rashes (including Stevens-Johnson syndrome). The risk is higher with fast dose increases, so it is started low and raised slowly — report any new rash immediately.
Valproate: carries FDA boxed warnings for serious liver damage, pancreas damage, and birth defects; it can seriously harm a developing fetus.
Carbamazepine: can lower blood-cell counts and carries a serious skin-reaction risk (higher with certain genetic markers), so people on it are monitored.

Antipsychotics

What they treat: psychotic disorders such as schizophrenia and schizoaffective disorder; some are also used as mood stabilizers in bipolar disorder, and some are added for severe or hard-to-treat depression.
Examples: aripiprazole, risperidone, quetiapine, olanzapine, lurasidone, ziprasidone (second-generation); haloperidol, fluphenazine, perphenazine (first-generation); and clozapine (used when others haven’t worked).
How they work: reduce signaling at certain dopamine receptors; many second-generation ones also act on serotonin receptors.
Common side effects: movement effects (restlessness, stiffness, tremor, slowed movement); metabolic effects (weight, blood sugar, cholesterol — which are monitored); and sedation.
Key safety: long-term use can cause tardive dyskinesia (repetitive, uncontrollable movements), so new movements should be reported early. Clozapine needs regular blood tests because of a rare, dangerous drop in white blood cells. There is also a boxed warning about increased risk of death in older adults with dementia-related psychosis.

Stimulants

Stimulants are the most common medicines for ADHD. They increase dopamine and norepinephrine activity to help with focus and attention, and they come in short-acting and long-acting forms. They are controlled medicines, prescribed and monitored carefully.

Short-acting forms work for a few hours, so they may be taken more than once a day. Examples include methylphenidate (Ritalin), dexmethylphenidate (Focalin), and amphetamine/dextroamphetamine (Adderall).
Long-acting forms release the medicine gradually and are designed to last through the day from a single morning dose. Examples include Concerta, Adderall XR, and lisdexamfetamine (Vyvanse).
Common side effects: reduced appetite, trouble sleeping, weight loss, irritability, headache, stomachache, and sometimes tics.
Key safety: stimulants are controlled medicines (Schedule II) with a potential for misuse. Heart rate, blood pressure, and growth are monitored, and a prescriber asks about any heart conditions.

Anti-anxiety medications

For most anxiety disorders, SSRIs and SNRIs are the first-line medication, usually alongside therapy. Other medicines are used in specific situations.

Benzodiazepines

What they treat: short-term relief of some anxiety symptoms, sometimes for a limited time while a longer-term treatment takes effect. They are not a first-choice, long-term anxiety treatment.
Examples: alprazolam (Xanax), lorazepam (Ativan), diazepam (Valium), clonazepam (Klonopin), chlordiazepoxide (Librium).
How they work: boost GABA, a calming neurotransmitter, and act quickly.
Common side effects: drowsiness, dizziness, poor concentration, memory problems, and unsteadiness.
Key safety: they can cause tolerance and physical dependence even when taken as prescribed, over days to weeks, and stopping suddenly can cause serious withdrawal (including seizures) — so they are tapered, never stopped abruptly. A 2020 FDA boxed warning covers the risks of misuse, dependence, and withdrawal, and the danger of combining them with opioids, alcohol, or other sedatives (severe sleepiness, slowed breathing, coma, or death). Used carefully, they are still a legitimate treatment.

Other anti-anxiety options

Buspirone treats generalized anxiety, is taken regularly rather than as-needed, and does not cause benzodiazepine-type dependence; it can cause dizziness, nausea, or headache.
Hydroxyzine is an antihistamine sometimes used for short-term anxiety; it is not habit-forming, and its main side effect is drowsiness.

Talk to a professional

Nothing here is a recommendation. Medication decisions belong with a prescriber who knows you. If you are in crisis, call or text 988 (US), or see the crisis help page.

Are you a licensed clinician, pharmacist, or other qualified healthcare professional?

We’re reviewing and improving these resources, and we’d love your help. If you’re interested in advising Sophrosyne or reviewing our educational content, please reach out at sophrosynementalhealth@gmail.com.

Sources

NIMH — Mental Health Medications
FDA — Suicidality in Children and Adolescents Being Treated With Antidepressant Medications (the antidepressant boxed warning)
FDA — Boxed Warning updated to improve safe use of the benzodiazepine drug class (2020)
MedlinePlus — Lithium
MedlinePlus — Lamotrigine
MedlinePlus — Valproic Acid

Sources were last checked October 2026. Every source links to the exact document cited, never a homepage.