DepressionMedications for Depression
A patient reference guide from Tailor Made Psychiatry
About These Medications
Depression is a complex condition shaped by biology, life experiences, relationships, stress, sleep, and physical health. It is not simply caused by a 'chemical imbalance.' Medications work by altering neurochemical activity in the brain in ways that can make the condition more manageable — but they are rarely the whole answer. Most people do best when medication is combined with therapy and attention to the broader factors that contributed to the episode.
Read the class information block before looking up your specific medication — it covers side effects and timelines that apply to all drugs in that group.
SSRIs — Selective Serotonin Reuptake Inhibitors
SSRIs are the most commonly prescribed first-line medications for depression in Canada (CANMAT 2023). They are generally well tolerated and have a broad evidence base.
Common class side effects
- Nausea or loose stools — usually improves within the first 1–2 weeks; take with food
- Headache, especially in the first week or two
- Insomnia or vivid dreams — usually settles; take in the morning
- Increased sweating
- Sexual side effects — reduced libido or delayed orgasm; common and worth discussing if bothersome
- Mild increase in anxiety or restlessness in the first 1–2 weeks — this is expected and settles
Stopping this medication: Do not stop SSRIs suddenly. Because your brain adapts to these medications over time, stopping abruptly can cause discontinuation symptoms: dizziness, flu-like feelings, irritability, or 'brain zaps.' Always taper gradually with your doctor's guidance.
What to expect — SSRIs
Weeks 1–2Side effects may appear before any benefit. Nausea and restlessness are common. This is the hardest week — many people feel tempted to stop.
Weeks 2–4First signs of improvement often appear: sleep may become more regular, energy or motivation may begin to lift. Mood itself often lags behind.
Weeks 4–8Fuller mood improvement by weeks 6–8. Give a full 8 weeks before concluding a medication is not working.
Sertraline — Zoloft
Distinct features
Broad evidence base across depression, anxiety, and PTSD. One of the most widely used SSRIs.
Watch for
Loose stools more common than with other SSRIs — usually settles within 2 weeks.
Escitalopram — Cipralex
Distinct features
Among the most selective SSRIs with a very clean tolerability profile. A common first choice.
Watch for
At higher doses, may affect heart rhythm (QT interval) — relevant if you have a heart condition or take other medications. Inform your doctor of all medications you take.
Fluoxetine — Prozac
Distinct features
Very long-acting — stays in the body for weeks. Missed doses have less immediate impact. More activating than other SSRIs.
Watch for
More likely to cause insomnia or agitation early on. Interacts with many other medications — always inform your pharmacist you are taking it.
SNRIs — Serotonin-Norepinephrine Reuptake Inhibitors
SNRIs work on both serotonin and norepinephrine. They are a strong first-line option, particularly when fatigue, pain, or concentration difficulties are prominent alongside low mood.
Common class side effects
- Nausea — take with food; usually improves within 1–2 weeks
- Increased sweating
- Dry mouth and constipation
- Sexual side effects similar to SSRIs
- Mild increase in blood pressure — more relevant at higher doses
Stopping this medication: SNRIs have a more noticeable discontinuation syndrome than SSRIs. Do not stop suddenly. Symptoms include dizziness, 'brain zaps,' flu-like feelings, and irritability. Taper slowly and under guidance.
What to expect — SNRIs
Weeks 1–2Similar early side effect pattern to SSRIs. Nausea and sweating most prominent in week 1.
Weeks 2–4Energy and concentration often improve before mood. Sleep may stabilize.
Weeks 4–8Full antidepressant effect typically by weeks 6–8.
Venlafaxine XR — Effexor XR
Distinct features
The norepinephrine effect increases at higher doses — may feel more activating as the dose is raised. Effective for anxiety alongside depression.
Watch for
Blood pressure — check periodically, especially above 150 mg/day. One of the more significant discontinuation syndromes among antidepressants if stopped abruptly.
Duloxetine — Cymbalta
Distinct features
More balanced dual action across the dose range. Also used for chronic pain conditions — may help if pain is part of the picture.
Watch for
Avoid with heavy alcohol use (liver effects). Discontinuation symptoms are significant — always taper.
Desvenlafaxine — Pristiq
Distinct features
Fixed-dose tablet; simpler dosing than venlafaxine. Consistent effect across the dose range.
Watch for
Discontinuation symptoms similar to venlafaxine — taper gradually.
Other Antidepressants
These medications work through different mechanisms and have distinct profiles. Read the entry for your specific medication.
About this group
- Each works differently from the SSRIs and SNRIs above
- Side effects, timelines, and 'what to expect' differ by medication — see each entry
Stopping this medication: As with all antidepressants, do not stop these suddenly — plan any changes with your doctor.
Bupropion XL — Wellbutrin XL
What makes it different
Acts on dopamine and norepinephrine — no serotonin effect. More activating than most antidepressants. No sexual side effects. May help with smoking cessation.
Common side effects
Insomnia, dry mouth, reduced appetite, headache, agitation — especially early on.
Timeline
Energy and motivation often improve first, around weeks 2–4. Mood improvement follows at weeks 4–8.
Watch for
Do not use if you have a seizure disorder, active eating disorder with purging, or heavy alcohol use — lowers seizure threshold.
Mirtazapine — Remeron
What makes it different
Sedating, particularly at lower doses. Increases appetite. No sexual side effects. Often chosen when poor sleep, poor appetite, or significant anxiety accompanies depression.
Common side effects
Sedation (often significant early on), increased appetite and weight gain, dry mouth, constipation.
Timeline
Sleep improvement often within the first week — one of the earliest-acting effects. Mood improvement at weeks 2–4.
Watch for
Weight gain can be substantial over time — worth monitoring and discussing with your doctor if it becomes a concern.
Vortioxetine — Trintellix
What makes it different
A 'multimodal' antidepressant — it acts on serotonin in more than one way. Often chosen for its low rate of sexual side effects and for a possible benefit on concentration and mental clarity. Very long-acting, so missed doses and stopping are less likely to cause discontinuation symptoms.
Common side effects
Nausea is the most common (dose-related; take with food, usually eases over 1–2 weeks). Headache or dry mouth are less common.
Timeline
Like other antidepressants — first changes around weeks 2–4, with fuller effect by weeks 6–8.
Watch for
Nausea is the main early issue and usually settles. As with all antidepressants, tell your doctor early about new or worsening agitation or thoughts of self-harm.
Finding the Right Medication
It is common to need more than one try before finding the medication and dose that works best for you. This is a normal part of the process — not a sign of failure. If a medication is not helping after a full trial, or side effects are not manageable, there are other options. Keep your doctor informed about how you are responding so adjustments can be made.
When to Seek Help
Go to the emergency department or call 911 if you experience:
- Thoughts of suicide with a plan or intent — call 988 (Suicide Crisis Helpline) or go to the nearest emergency department
- Signs of serotonin syndrome (see below) — a rare but serious reaction, most likely if combining multiple serotonergic medications
- Severe allergic reaction: rash, facial swelling, difficulty breathing
Serotonin Syndrome — signs to know
- Agitation, confusion, or restlessness
- Rapid heart rate and high blood pressure
- Muscle twitching, rigidity, or loss of coordination
- High fever, sweating, or shivering
These symptoms together — especially after starting or increasing a medication — require immediate medical attention.