What You Need to Know About Your Antidepressant Medication

Why are they prescribed?

Antidepressants are most commonly prescribed for major depression. They are also FDA-approved for many anxiety disorders (generalized anxiety, social anxiety, panic disorder, obsessive-compulsive disorder, post-traumatic stress disorder), as well as certain pain conditions and other uses depending on the specific medication. Some antidepressants are used off-label for insomnia, migraines, nerve pain, or hot flashes.

Types and medication names:

• SSRIs (Selective Serotonin Reuptake Inhibitors): fluoxetine (Prozac), sertraline (Zoloft), citalopram (Celexa), escitalopram (Lexapro), paroxetine (Paxil), fluvoxamine (Luvox)

• SNRIs (Serotonin-Norepinephrine Reuptake Inhibitors): venlafaxine (Effexor), duloxetine (Cymbalta), desvenlafaxine (Pristiq), levomilnacipran (Fetzima)

• Others: bupropion (Wellbutrin), mirtazapine (Remeron), trazodone (Desyrel), vortioxetine (Trintellix), vilazodone (Viibryd)

• Older classes (used less often): tricyclic antidepressants such as amitriptyline, nortriptyline, imipramine; MAOIs such as phenelzine (Nardil), tranylcypromine (Parnate)

When do they start working?

Some improvement may be noticed within 1–2 weeks, but full effects often take 4–8 weeks (and sometimes up to 12 weeks). It is important to keep taking the medication even if you do not feel better right away. Side effects like nausea and headache often improve within the first 1–2 weeks.

Common side effects:

• SSRIs/SNRIs: nausea, headache, dizziness, insomnia or drowsiness, sexual dysfunction (decreased desire, difficulty with orgasm), weight changes, increased sweating

• Bupropion: dry mouth, insomnia, headache, nausea (less likely to cause sexual side effects or weight gain)

• Mirtazapine: drowsiness, increased appetite, weight gain

• Trazodone: drowsiness, dizziness, dry mouth

Important warnings:

• All antidepressants carry an FDA Black Box Warning about the possibility of increased suicidal thoughts or behavior, especially in children, teens, and young adults under age 25 during the first few weeks of treatment or after dose changes. Report any new or worsening mood changes, agitation, or suicidal thoughts to your provider immediately.

• Do not stop your antidepressant suddenly. Stopping abruptly can cause discontinuation symptoms such as dizziness, nausea, "electric shock" sensations, irritability, and insomnia. Your provider can help you taper off gradually.

• Serotonin syndrome is a rare but serious reaction that can occur when combining serotonin-affecting medications. Symptoms include agitation, confusion, rapid heartbeat, fever, and muscle twitching. Seek emergency care if these occur.

• MAOIs require strict dietary restrictions (avoiding aged cheeses, cured meats, and certain other foods) to prevent dangerous blood pressure spikes.

There are several types of anti-anxiety medications. Your provider will choose the best option based on your specific diagnosis, other medications, and medical history.

A. SSRIs and SNRIs (First-Line Treatment for Anxiety)

SSRIs and SNRIs (listed above under Antidepressants) are considered the first-line medication treatment for most anxiety disorders, including generalized anxiety disorder, social anxiety disorder, panic disorder, and others. Even though they are called "antidepressants," they are very effective for anxiety — you do not need to have depression for them to help. See the Antidepressants section above for details on these medications.

B. Buspirone (BuSpar)

Why is it prescribed?

Buspirone is FDA-approved for generalized anxiety disorder (GAD). It is a non-addictive anti-anxiety medication that works differently from benzodiazepines. It is sometimes used alone or added to an antidepressant when anxiety has not fully responded.

When does it start working?

Buspirone takes time to work — usually 2–4 weeks for noticeable improvement. However, it is sometimes used for acute anxiety, though evidence to support its efficacy is limited.

Common side effects:

• Dizziness

• Nausea

• Headache

• Drowsiness

• Nervousness or excitement (usually temporary)

• Lightheadedness

Important warnings:

• Buspirone does not cause physical dependence or withdrawal symptoms, which is a major advantage over benzodiazepines.

• It will not work if taken only "as needed" — it must be taken consistently every day.

• If you have previously taken benzodiazepines, buspirone may seem less effective because it works more gradually and does not produce the immediate calming sensation.

• Do not take buspirone with MAOIs (a type of antidepressant). There is a risk of dangerous blood pressure increases.

• Take buspirone consistently — always with food or always without food — because food affects how much medication your body absorbs.

C. Hydroxyzine (Vistaril, Atarax)

Why is it prescribed?

Hydroxyzine is an antihistamine that is FDA-approved for anxiety and tension. It is sometimes used for short-term or as-needed anxiety relief, especially when benzodiazepines are not appropriate (for example, in patients with a history of substance use). It is also commonly used for itching and as a sleep aid.

When does it start working?

Hydroxyzine works relatively quickly — usually within 30–60 minutes. It can be taken on an as-needed basis or on a regular schedule.

Common side effects:

• Drowsiness (the most common side effect)

• Dry mouth

• Dizziness

• Headache

• Blurred vision

Important warnings:

• Hydroxyzine is not habit-forming and does not carry a risk of dependence.

• Because it causes drowsiness, use caution when driving or operating machinery, especially when you first start taking it.

• Hydroxyzine can prolong the QTc interval on an EKG in some patients, so tell your provider if you have heart rhythm problems.

• It is generally not recommended as a first-line long-term treatment for anxiety disorders.

D. Benzodiazepines

Why are they prescribed?

Benzodiazepines are FDA-approved for anxiety disorders (generalized anxiety, panic disorder, social phobia), insomnia, seizures, alcohol withdrawal, and muscle spasms. They are also used for acute agitation and procedural sedation. They work quickly and are often used for short-term or as-needed relief.

Medication names:

• alprazolam (Xanax)

• lorazepam (Ativan)

• clonazepam (Klonopin)

• diazepam (Valium)

• temazepam (Restoril) — primarily for insomnia

• chlordiazepoxide (Librium) — often used for alcohol withdrawal

• midazolam (Versed) — used for procedural sedation

When do they start working?

Benzodiazepines work quickly — usually within 15–60 minutes. This rapid onset is one of their main advantages for acute anxiety or panic.

Common side effects:

• Drowsiness and sedation

• Dizziness and unsteadiness

• Slowed thinking, memory problems

• Fatigue

Important warnings:

• Benzodiazepines carry an FDA Black Box Warning about the risk of physical dependence, withdrawal, and misuse. The body can become physically dependent on these medications, even when taken as prescribed.

• Never stop benzodiazepines suddenly after regular use. Abrupt discontinuation can cause serious and potentially life-threatening withdrawal symptoms, including seizures. Your provider will help you taper off slowly if needed.

• Combining benzodiazepines with opioids, alcohol, or other sedating substances greatly increases the risk of dangerous sedation, respiratory depression, and death.

• Benzodiazepines increase the risk of falls, especially in older adults.

• Long-term use may impair memory and cognitive function.

• These medications are generally recommended for short-term use (ideally less than 4 weeks) when possible.

E. Gabapentinoids (Gabapentin and Pregabalin)

Why are they prescribed?

Gabapentin (Neurontin) and pregabalin (Lyrica) are anticonvulsant (anti-seizure) medications that are sometimes used off-label for anxiety. They are not FDA-approved for anxiety disorders in the United States. However, pregabalin is approved for generalized anxiety disorder in Europe and has good evidence supporting its use. Gabapentin has less evidence for anxiety but is sometimes prescribed off-label. Both are also used for nerve pain, fibromyalgia, and seizures.

When do they start working?

Pregabalin may begin to reduce anxiety symptoms within the first week. Gabapentin may also work relatively quickly, though the timeline varies.

Common side effects:

• Drowsiness/sedation

• Dizziness

• Weight gain

• Swelling in the hands or feet (peripheral edema)

• Blurred vision

• Difficulty concentrating

Important warnings:

• Although gabapentinoids were initially thought to have low addiction potential, there are increasing reports of misuse, especially in people with a history of substance use disorders. Use caution and take only as prescribed.

• Do not stop these medications suddenly, as withdrawal symptoms (including anxiety, insomnia, and rarely seizures) can occur. Your provider will help you taper off gradually.

• Combining gabapentinoids with opioids, benzodiazepines, or alcohol increases the risk of dangerous sedation and breathing problems.

• Dose adjustments are needed for patients with kidney problems.

F. Beta-Blockers (Propranolol, Atenolol)

Why are they prescribed?

Beta-blockers are heart and blood pressure medications that are sometimes used off-label for performance anxiety (also called "stage fright") — for example, before public speaking, musical performances, or presentations. They are not FDA-approved for anxiety disorders and are not effective for generalized anxiety, panic disorder, or other anxiety conditions.

How are they used?

A single dose of propranolol (typically 10–40 mg) is taken about 30–60 minutes before a performance or anxiety-provoking event. They are used on an as-needed basis, not daily.

How do they work?

Beta-blockers do not reduce the mental or emotional experience of anxiety. Instead, they block the physical symptoms of anxiety — such as rapid heartbeat, trembling, sweating, and shaky voice — by blocking the effects of adrenaline.

Common side effects:

• Lightheadedness or dizziness

• Fatigue

• Cold hands and feet

• Slow heart rate

Important warnings:

• Beta-blockers should not be used by people with asthma, very low heart rate, or certain heart conditions without medical guidance.

• They can lower blood pressure, so use caution if you already have low blood pressure or take blood pressure medications.

• It is a good idea to try a "test dose" at home before using a beta-blocker in a performance situation, so you know how it affects you.

• Beta-blockers do not treat the underlying anxiety disorder — they only manage physical symptoms in specific situations.

Why are they prescribed?

Antipsychotics are FDA-approved for schizophrenia and bipolar disorder (mania, mixed episodes, and in some cases bipolar depression). Several are also approved as add-on treatment for major depression that has not responded to antidepressants alone. They are sometimes used off-label for severe anxiety, insomnia, agitation, or behavioral symptoms in dementia.

Types and medication names:

• Second-generation (atypical) antipsychotics: aripiprazole (Abilify), quetiapine (Seroquel), risperidone (Risperdal), olanzapine (Zyprexa), ziprasidone (Geodon), lurasidone (Latuda), paliperidone (Invega), cariprazine (Vraylar), brexpiprazole (Rexulti), asenapine (Saphris), clozapine (Clozaril)

• First-generation (typical) antipsychotics: haloperidol (Haldol), chlorpromazine (Thorazine), fluphenazine, perphenazine

When do they start working?

Some calming effects may be noticed within hours to days, but full improvement in symptoms like hallucinations, delusions, or mood instability typically takes 2–6 weeks.

Common side effects:

• Weight gain and increased appetite (especially olanzapine, quetiapine, clozapine)

• Drowsiness/sedation

• Dizziness or lightheadedness when standing up (orthostatic hypotension)

• Movement-related side effects: muscle stiffness, tremor, restlessness (akathisia), involuntary movements. These are more common with first-generation antipsychotics but can occur with any.

• Metabolic effects: increased blood sugar, increased cholesterol/triglycerides

Important warnings:

• Antipsychotics carry an FDA Black Box Warning against use in elderly patients with dementia-related psychosis due to an increased risk of death.

• Tardive dyskinesia (involuntary movements of the face, tongue, or body) can develop with long-term use. Report any unusual movements to your provider.

• Some antipsychotics can prolong the QTc interval on an EKG, which may affect heart rhythm.

• Clozapine requires regular blood monitoring because it can cause a dangerous drop in white blood cells (agranulocytosis).

• Neuroleptic malignant syndrome (NMS) is a rare but life-threatening reaction causing high fever, muscle rigidity, confusion, and rapid heartbeat. Seek emergency care immediately.

• Do not stop antipsychotic medications suddenly without medical guidance, as this can cause withdrawal symptoms or a return of symptoms.

Why are they prescribed?

Mood stabilizers are primarily used to treat bipolar disorder — to manage manic episodes, prevent mood swings, and in some cases treat or prevent depressive episodes. Lithium is also used to reduce the risk of suicide in bipolar disorder. Some mood stabilizers (valproate, carbamazepine, lamotrigine) are also FDA-approved as anti-seizure medications.

Medication names:

• Lithium (Lithobid, Eskalith)

• Valproate/divalproex (Depakote)

• Lamotrigine (Lamictal)

• Carbamazepine (Tegretol, Equetro)

When do they start working?

Lithium and valproate may begin to reduce manic symptoms within 1–2 weeks, but full stabilization often takes several weeks. Lamotrigine must be started at a very low dose and increased slowly over several weeks, so its full effect may not be felt for 4–6 weeks or longer.

Common side effects:

• Lithium: tremor, increased thirst and urination, nausea, weight gain, drowsiness, mild cognitive dulling

• Valproate: nausea, weight gain, tremor, drowsiness, hair thinning

• Lamotrigine: headache, dizziness, nausea (generally well tolerated)

• Carbamazepine: dizziness, drowsiness, nausea, blurred vision

Important warnings:

• Lithium has a narrow therapeutic window — the difference between a helpful dose and a toxic dose is small. Regular blood tests are required to monitor lithium levels, kidney function, and thyroid function. Signs of lithium toxicity include severe nausea/vomiting, diarrhea, confusion, unsteadiness, and tremor. Stay well hydrated and maintain consistent salt intake. Avoid sudden changes in fluid or salt intake.

• Valproate carries an FDA Black Box Warning for liver toxicity (especially in children under 2), pancreatitis, and serious birth defects. It should generally be avoided in women who are pregnant or may become pregnant.

• Lamotrigine must be started slowly because of the risk of serious skin reactions, including Stevens-Johnson syndrome (a rare but potentially life-threatening rash). Contact your provider immediately if you develop a rash, especially with fever, mouth sores, or blistering.

• Carbamazepine can cause serious skin reactions and a dangerous drop in blood cell counts (agranulocytosis, aplastic anemia). It also interacts with many other medications. It should be avoided in pregnancy due to risk of birth defects.

Why are they prescribed?

Stimulants are FDA-approved for attention-deficit/hyperactivity disorder (ADHD) in children, adolescents, and adults. Some formulations are also approved for narcolepsy. They are the first-line treatment for ADHD, with approximately 70% of patients experiencing significant improvement.

Medication names:

• Methylphenidate-based: methylphenidate (Ritalin, Concerta, Daytrana patch), dexmethylphenidate (Focalin)

• Amphetamine-based: mixed amphetamine salts (Adderall), lisdexamfetamine (Vyvanse), dextroamphetamine (Dexedrine)

Non-stimulant alternatives (for patients who cannot take stimulants):

• atomoxetine (Strattera)

• guanfacine extended-release (Intuniv)

• clonidine extended-release (Kapvay)

• viloxazine (Qelbree)

When do they start working?

Stimulants work very quickly — effects are typically noticed within 30–60 minutes of taking a dose. Immediate-release formulations last about 3–6 hours; extended-release formulations last 8–12 hours. Non-stimulant medications take longer, often 2–6 weeks, to reach full effect.

Common side effects:

• Decreased appetite and weight loss

• Insomnia or difficulty falling asleep

• Headache

• Dry mouth

• Stomach pain or nausea

• Mild increases in heart rate and blood pressure

• Irritability or anxiety

Important warnings:

• Stimulants are classified as Schedule II controlled substances due to their potential for misuse and dependence. Take them only as prescribed and store them securely.

• Before starting a stimulant, tell your provider about any history of heart problems, high blood pressure, or family history of sudden cardiac death, heart rhythm problems, or cardiomyopathy.

• Stimulants can worsen tics, psychosis, or severe anxiety in some individuals.

• Long-term stimulant use in children may modestly reduce adult height (by approximately 1–2 cm).

• Stimulants carry an FDA warning about the potential for cardiovascular events, though large studies have not shown an increased risk of serious events in people without pre-existing heart conditions.

Sleep problems are very common and can be caused by many factors. Before starting a sleep medication, your provider should evaluate for underlying causes of poor sleep (such as sleep apnea, pain, medications, or habits that interfere with sleep). Non-medication treatments — especially cognitive behavioral therapy for insomnia (CBT-I) — are considered the most effective first-line treatment for chronic insomnia. Sleep medications are typically used when CBT-I is not available, not effective, or as a short-term bridge while behavioral strategies take effect.

A. Z-Drugs (Non-Benzodiazepine Sleep Aids)

Why are they prescribed?

Z-drugs are FDA-approved for insomnia. They help you fall asleep faster and, depending on the specific medication, may also help you stay asleep. They work on the same brain receptors as benzodiazepines but are designed to be more targeted for sleep.

Medication names:

• zolpidem (Ambien) — also available in extended-release (Ambien CR) and sublingual forms (Edluar, Intermezzo)

• zaleplon (Sonata) — ultra-short acting, best for trouble falling asleep

• eszopiclone (Lunesta) — longer acting, helps with both falling asleep and staying asleep

When do they start working?

Z-drugs work quickly — usually within 15–30 minutes. They should be taken immediately before bedtime, and only when you can devote 7–8 hours to sleep. Zaleplon has such a short duration that it can even be taken after a middle-of-the-night awakening.

Common side effects:

• Drowsiness and next-day grogginess (especially with longer-acting agents)

• Dizziness

• Headache

• Unpleasant taste (especially eszopiclone)

• Nausea

• Memory problems (especially if you do not get a full night's sleep)

Important warnings:

• Z-drugs carry an FDA Black Box Warning for complex sleep behaviors — including sleepwalking, sleep-driving, sleep-eating, and other activities while not fully awake. These can occur even at the lowest dose and after the first use. If you experience any of these, stop the medication and contact your provider immediately.

• Tolerance and physical dependence can develop with regular nightly use. Stopping suddenly after regular use can cause rebound insomnia (temporarily worse sleep than before you started the medication).

• Do not take Z-drugs with alcohol, opioids, or other sedating medications — this combination can be dangerous.

• Use the lowest effective dose. Women are generally prescribed lower doses than men because they metabolize these drugs more slowly.

• Older adults are at increased risk for falls and confusion with these medications.

B. Orexin Receptor Antagonists (DORAs)

Why are they prescribed?

These are a newer class of sleep medications that are FDA-approved for insomnia — both difficulty falling asleep and difficulty staying asleep. They work by blocking orexin, a brain chemical that promotes wakefulness. They are considered to have a lower risk of dependence and less cognitive impairment compared to Z-drugs and benzodiazepines.

Medication names:

• suvorexant (Belsomra)

• lemborexant (Dayvigo)

• daridorexant (Quviviq)

When do they start working?

These medications typically work within 30 minutes and should be taken within 30 minutes of bedtime, with at least 7 hours remaining before you need to wake up.

Common side effects:

• Drowsiness/next-day sleepiness

• Headache

• Dizziness

• Abnormal or vivid dreams, nightmares

• Sleep paralysis (brief inability to move when falling asleep or waking up — uncommon but can be frightening)

Important warnings:

• These medications should not be used by people with narcolepsy, because they block the same brain chemical (orexin) that is already deficient in narcolepsy.

• Like all sleep medications, they carry an FDA warning about complex sleep behaviors (sleepwalking, sleep-driving, etc.).

• They do not appear to cause significant tolerance, withdrawal, or rebound insomnia when stopped — a key advantage over Z-drugs and benzodiazepines.

• Avoid alcohol and other sedating medications while taking these drugs.

• Tell your provider if you experience worsening depression or suicidal thoughts.

C. Melatonin and Melatonin Receptor Agonists

Why are they prescribed?

Melatonin is a natural hormone your body produces to signal that it is time to sleep. Melatonin supplements (available over the counter) and the prescription melatonin receptor agonist ramelteon (Rozerem) are used primarily for difficulty falling asleep. They are not very effective for staying asleep.

Medication names:

• Melatonin (over-the-counter supplement) — available in many doses (typically 0.5–10 mg)

• Ramelteon (Rozerem) — FDA-approved for insomnia characterized by difficulty with sleep onset

When do they start working?

Melatonin and ramelteon should be taken 30–60 minutes before bedtime. They may help you fall asleep somewhat faster, but the effect is generally modest. Ramelteon may take several nights of consistent use to reach full effect.

Common side effects:

• Drowsiness

• Dizziness

• Fatigue

• Headache

• Nausea

Important warnings:

• Melatonin and ramelteon have very few serious side effects and no risk of dependence — they are among the safest sleep medications available.

• Melatonin supplements are not regulated by the FDA the same way prescription drugs are. Studies have found that the actual melatonin content in supplements can vary widely from what is listed on the label.

• Ramelteon should not be taken with fluvoxamine (Luvox), which dramatically increases ramelteon levels in the blood.

• These medications are best suited for people who have trouble falling asleep, not for those who wake up frequently during the night.

D. Low-Dose Doxepin (Silenor)

Why is it prescribed?

Doxepin at very low doses (3–6 mg) is FDA-approved for insomnia, specifically for difficulty staying asleep. At these low doses, it works as an antihistamine to promote sleep — this is a much lower dose than what is used for depression (75–300 mg). It is one of the best-tolerated prescription sleep medications.

When does it start working?

Low-dose doxepin works within about 30 minutes. It should be taken within 30 minutes of bedtime, and not within 3 hours of a meal (food can increase the medication's effects and cause excessive drowsiness).

Common side effects:

• Drowsiness/sedation

• Nausea

• Upper respiratory infection symptoms

Side effects are generally mild at the low doses used for insomnia.

Important warnings:

• Low-dose doxepin has a low risk of dependence and does not cause rebound insomnia when stopped.

• Although higher doses of doxepin (used for depression) carry an FDA Black Box Warning about suicidal thoughts, the risk at the very low doses used for insomnia is not well established.

• It is a good option for older adults because it is not on the Beers Criteria list of medications to avoid in people 65 and older (unlike Z-drugs and benzodiazepines).

E. Trazodone (Used Off-Label for Sleep)

Why is it prescribed?

Trazodone is an antidepressant that is very commonly prescribed off-label at low doses (25–100 mg) as a sleep aid. It is not FDA-approved for insomnia, and the evidence for its effectiveness as a sleep medication is inconsistent. However, many providers prescribe it because it is inexpensive, generally well tolerated, and has a low risk of dependence.

When does it start working?

Trazodone typically causes drowsiness within 30–60 minutes.

Common side effects:

• Drowsiness

• Dizziness or lightheadedness

• Dry mouth

• Headache

• Blurred vision

Important warnings:

• Trazodone can cause a drop in blood pressure when standing up (orthostatic hypotension), which increases the risk of falls — especially in older adults.

• In rare cases, trazodone can cause priapism (a prolonged, painful erection) in men. This is a medical emergency — seek immediate care if this occurs.

• As an antidepressant, it carries the FDA Black Box Warning about suicidal thoughts in young adults, though this risk at the low doses used for sleep is not well studied.

• Current guidelines generally do not recommend trazodone as a first-line sleep medication due to limited evidence, but it remains widely used in practice.

F. Over-the-Counter Sleep Aids (Antihistamines)

Why are they used?

Diphenhydramine (Benadryl, ZzzQuil, Tylenol PM) and doxylamine (Unisom SleepTabs) are antihistamines available without a prescription that cause drowsiness. Many people use them as sleep aids. However, there is limited evidence that they are effective for insomnia, and they are not recommended for regular use.

When do they start working?

These medications typically cause drowsiness within 30–60 minutes.

Common side effects:

• Drowsiness (can last into the next day — "hangover" effect)

• Dry mouth

• Constipation

• Blurred vision

• Urinary retention (difficulty urinating)

• Confusion (especially in older adults)

Important warnings:

• These medications are not recommended for older adults (age 65+) due to increased risk of confusion, falls, urinary retention, and possible association with long-term cognitive decline (dementia).

• Tolerance develops quickly — they tend to become less effective after a few days of regular use.

• They have anticholinergic effects that can be harmful, especially in people with glaucoma, enlarged prostate, or certain heart conditions.

• They are not recommended for chronic insomnia by any major medical guideline.