The First Weeks on Antidepressants: What’s Normal and When to Call Your Doctor

How Antidepressants Work and Why the Effect Isn’t Immediate

Most modern antidepressants affect signaling involving serotonin, norepinephrine and other neurotransmitters. Chemical changes at the synapses begin after the first doses, but clinical improvement takes time: the brain needs to readjust its receptors and the neural networks involved in regulating mood, stress and sleep. That is why an antidepressant does not work like a painkiller that helps within half an hour.

The typical sequence of changes is as follows: first sleep and appetite improve and a little energy appears, then anxiety decreases, and only after that does mood even out. Sometimes the people around you notice the improvement before you do. It is important to know about this sequence so as not to become disappointed with treatment in the first days and stop taking the medication before it has had a chance to work.

Which Side Effects Are Normal in the First Weeks

Side effects at the start of treatment are common and in most cases mild and temporary. The body adapts to the medication, and after one or two weeks many effects weaken or disappear. Which effects occur and how strong they are depends on the class of antidepressant and individual factors, so the doctor tells you in advance what to expect from your particular treatment.

Why You Might Feel More Anxious

In some people, anxiety increases briefly at the start of treatment: inner tension, restlessness and sleep problems appear. This is related to the nervous system adapting to the medication. The doctor may start treatment at a low dose and increase it gradually to reduce this effect. If the anxiety is severe or accompanied by an inability to sit still, tell your doctor.

What to Do About Unpleasant Effects

Don’t stop taking the medication on your own. Contact your doctor: often it is enough to change the time you take it, take it with food, or temporarily adjust the dose or regimen. Keep short notes — what the effect is, when it started and how severe it is. This will help the doctor understand whether something needs to change or whether it is worth waiting for your body to adjust.

• Nausea, stomach discomfort, changes in bowel habits — often reduced by taking the medication with food
• Headache, usually mild and passing within the first days
• Drowsiness or, conversely, difficulty falling asleep and vivid dreams
• A temporary increase in anxiety or inner restlessness in the first days
• Dry mouth, increased sweating, especially at night
• Mild dizziness, especially when standing up quickly
• Changes in appetite, reduced libido and sexual difficulties

When to Call Your Doctor Urgently

Some symptoms require immediate attention. First and foremost, this is the appearance or worsening of suicidal thoughts. At the start of treatment, especially in teenagers and young adults, energy may return before mood does, and this is a period that calls for extra vigilance. That is why doctors recommend that loved ones stay close and watch for changes. If such thoughts appear, it doesn’t mean the treatment is unsuitable, but you need to contact your doctor the same day, and if there is an intention to act, call 103 or 112.

Also tell your doctor urgently about a sudden rise in mood: if you are barely sleeping yet full of energy, talking a lot, spending money and making grandiose plans. This may indicate bipolar disorder. Signs of serotonin syndrome are also dangerous — a combination of agitation, confusion, severe tremor or muscle twitching, sweating, high fever and a rapid heartbeat. It most often occurs when several serotonergic medications are combined and requires emergency care.

• Thoughts of suicide appear or noticeably intensify
• Severe restlessness, agitation, a feeling that you can’t sit still
• A sudden rise in mood, sleeplessness without fatigue, risky behavior
• A rash, swelling of the face or lips, difficulty breathing
• Severe tremor, muscle twitching, high fever, confusion
• Fainting, a pounding heartbeat, bleeding or unusual bruising

What to Do in the First Weeks of Treatment

Take the medication every day at the same time, as prescribed by your doctor. Ask your doctor in advance what to do if you miss a dose: don’t double the dose on your own. Set reminders on your phone. Avoiding alcohol is especially important at the start of treatment: it increases drowsiness and dizziness, worsens sleep and in itself deepens depression, cancelling out the effect of therapy.

Tell every doctor you see that you are taking an antidepressant, and don’t start other medications — including painkillers, migraine medications, herbal remedies such as St. John’s wort, or supplements — without consulting your doctor, as interactions are possible. Be careful when driving in the first days until it is clear how the medication affects your attention. Continue psychotherapy if it has been prescribed, and keep up a regular routine of sleep and activity.

When the Effect Is Assessed and What to Do If There’s No Improvement

The doctor usually assesses the first changes after 2–4 weeks and effectiveness after 6–8 weeks at an adequate dose. If there is no improvement or only a weak one by then, the approach is reviewed: the dose is adjusted, the medication is switched to another one from the same or a different class, or psychotherapy or additional medications are added. Don’t be surprised if the first medication doesn’t suit you: finding the right treatment often takes more than one attempt.

Sometimes a lack of effect is due to an inaccurate diagnosis, such as unrecognized bipolar disorder, coexisting anxiety, alcohol use or a physical cause. That is why honesty at follow-up appointments matters. At Psychiatry Online, monitoring while you are on antidepressants takes place online with the same doctor, which is convenient in the first weeks, when contact is needed most often.

Myths About Antidepressants

“Antidepressants are addictive.” They don’t cause addiction in the way alcohol or tranquilizers do: a person doesn’t need to increase the dose to get the same effect and doesn’t experience cravings. But stopping abruptly can cause discontinuation syndrome, so the medication should be stopped gradually under a doctor’s supervision. “Antidepressants change your personality” — when properly selected, they bring a person back to their usual self rather than making them someone else.

“Once you start, you’ll have to take them for life” — no. The length of treatment depends on the number and severity of episodes. For most patients, therapy is discontinued after stable remission. “Pills are a sign of weakness” — depression is a medical condition, and treatment helps just as it does for any other illness. The decision to take medication is made together with the doctor on the basis of informed consent.

When to see a doctor

• Side effects haven’t eased after two weeks or are interfering with your normal life
• After 4–6 weeks of regular use, you don’t notice any improvement
• Thoughts of suicide have appeared or become stronger than before treatment
• You are barely sleeping but feel a surge of energy and are talking a lot
• You want to take another medication or supplement at the same time as the antidepressant
• You have found out you are pregnant or are planning a pregnancy while taking an antidepressant

Questions and answers

Reviewed by

Pavel Kornilov, MDPsychiatrist

Depression, anxiety disorders, OCD, bipolar disorder; online medication selection and adjustment.