Side effects of antidepressants


According to the variety of antidepressants, there are different side effects depending on the active ingredient. However, headaches are very common.

In addition to the desired mood-enhancing effect, antidepressants naturally also have side effects.
Interactions with other drugs must also be taken into account, as well as the presence of, for example, certain diseases that could be a contraindication.

The type of side effect depends heavily on the type of antidepressant you are taking.
Some of these undesirable effects are listed below according to the antidepressant. These are only a selection and occur in different frequencies.

Tricyclic and Tetracyclic Antidepressants (TCAs)

  • Dry mouth, increased sweating, nausea, a headache
  • Disorders of gastrointestinal function with constipation
  • Micturition disorders with Urinary retention
  • CNS symptoms such as disorientation, confusion, motor restlessness (also occur primarily in the case of intoxication with TCA)
  • Tripping epileptic seizures
  • Influence on the heart activity with Cardiac arrhythmias (also life-threatening in case of poisoning)
  • Blood formation disorders: a blood count should be checked every 1-2 months
  • absolute contraindications are the combination of all antidepressants with antidepressants of the MAO inhibitor group as well as one existing risk of suicide, as some TCAs have a psychomotor activating and driving effect
  • other contraindications: glaucoma, Urination disorders, Abuse of alcohol and sleeping pills, Epilepsy

Selective Serotonin Reuptake Inhibitors (SSRI)

  • psychotic arousal with fear, Restlessness
  • sleep disorders
  • nausea, Vomit, diarrhea
  • increased tendency to bleed
  • Syndrome of inadequate ADH secretion with weakness, dizziness, a headache
  • increased risk of deformities when taken in early pregnancy
  • here too Beware of suicide risk (see TZA)!

You can find more about SSRI and alcohol at: Citalopram and alcohol - are they compatible?

Norepinephrine and serotonin reuptake inhibitors (NSRI)

  • like SSRI
  • in addition, rise in blood pressure and heart rate
  • Triggering the Serotonin Syndrome

Alpha2 adrenergic receptor antagonists

  • Tiredness, drowsiness
  • Headache, dizziness, nausea
  • confusion
  • Dry mouth
  • Liver dysfunction
  • Changes in blood count

MAO (monoamine oxidase) inhibitors

MAO inhibitors are by their side effects second choice only and come especially at therapy-resistant depression and social phobias for use.

  • Dry mouth
  • sleep disorders
  • Anxiety, irritability, arousal
  • Dizziness, nausea
  • low blood pressure


Caution is also advised with lithium.
It has only a narrow therapeutic range. This means that the dose that works and the dose that can cause severe side effects and even coma are within a narrow range.
So must the concentration in the blood measured regularly to avoid possible side effects and consequences.
Side effects include:

  • Tremor of the hands
  • Hypothyroidism or Thyroid goiter with normal thyroid function
  • increased urination, increased thirst
  • Nausea, diarrhea
  • Weight gain
  • Changes in the EKG and EEG

At a acute poisoning With lithium, vomiting, severe diarrhea and mental confusion can even lead to seizures and even coma.

Side effects of antidepressants

Side effects in pregnancy

Studies have shown that depression is more common during pregnancy. These occur above all in the last third pregnancy. Concomitant weight loss or malnutrition are a risk factor for low birth weight. For this reason, the continuation of antidepressant therapy during pregnancy may be indicated.

So far, there are insufficient research results that confirm the safety of treatment with antidepressants during pregnancy. Nonetheless, experience and the individual studies carried out over the past few years and decades show that therapy with common antidepressants (tricyclic antidepressants, selective serotonin reuptake inhibitors) no increased risk for physical and mental developmental disorders of the baby. Individual antidepressant therapy agreed with the attending physician is required. A reduction in dose, a change of preparation or a switch to one psychotherapy can be indexed. The doctor and the patient must individually weigh up the benefits of a therapy and the associated risk.

In the drug therapy of depression during pregnancy, the tricyclic antidepressants and the SSRIs the means of first choice. The SSRIs represent the most frequently prescribed antidepressants due to their better tolerability and a slightly lower risk of suicide and they can also be used for long-term therapy. About the effect of Johannis herbs There are so far few study results on mother and child - potential effects on the birth process are being discussed.

Individual studies published in recent years show a typical one Withdrawal symptoms in the baby in the first days after birth. Of temporary Movement disorders, mild epileptic seizures, palpitations and sweats was reported. However, these symptoms subside spontaneously within a few days after birth. Nevertheless, it may be necessary to reduce the dose in the last few weeks before the birth. Further studies have a slightly increased risk for Premature births shown in long-term therapy with SSRIs. In addition, a connection between antidepressant therapy and brain development is also being discussed, as the changed serotonin levels in the baby's body can also influence the development of the brain. A slightly increased risk for autism and ADHD (Attention Deficit Hyperactivity Disorder) is discussed.

Side effects on the bladder

An organ that is often affected by side effects in antidepressant therapy is the bladder. Depending on the preparation, both a increased need to urinate with the symptoms of irritable bladder as well as increased urinary retention occur. The symptoms usually already begin a few days after starting therapy. The side effects often diminish continuously in the course of long-term therapy. Depending on the symptoms, the side effects can also be treated with medication and thus avoided. So far, there is no evidence of possible permanent damage to the bladder.

During therapy with tricyclic antidepressants (Amitriptyline, Clomipramine, Nortriptyline) by influencing the autonomic nervous system, the tension of the bladder sphincter changes. Both urinary retention (inability to empty the bladder with urinary congestion), which occurs mainly in men with an enlarged prostate, and a Urinary incontinence (with symptoms of irritable bladder) are possible.

When treating with SSRIs (especially DuloxetineDifficulties for the patient to empty the bladder (urinary retention) are also frequently reported.

Side effects on the eye

In rare cases, therapy with tricyclic antidepressants also leads to an increase in the Intraocular pressure. This is due to a change in the pupil size and the resulting obstructed outflow of aqueous humor. There is a risk of the development or worsening of narrow-angle glaucoma (green Star). Without treatment, there is a risk of permanent damage to the eye. In individual cases, surgery may also be required to treat glaucoma.

Many other side effects of the common antidepressants in the eye area are possible. However, these usually only occur very rarely and often in combination with an existing eye disease. For example, a Conjunctivitis are favored in long-term therapy with SSRIs.

Tremors as a side effect

Often, in the course of antidepressant therapy, there is a regular one Tremble. In principle, this side effect is common with all common antidepressants (tricyclic antidepressants, SSRIs, MAO inhibitors, etc.) and can vary from patient to patient. The hands are particularly affected. Because of this, there is a risk of confusion with one tremoras it can occur in other neurological disorders.

With the SSRIs, constant tremors can also occur as withdrawal symptoms when the respective preparation is stopped abruptly. However, the tremors usually subside within a short period of time (days to weeks). There are no long-term effects on the human body from trembling.

Side effects from alcohol

While taking any antidepressants (tricyclic antidepressants, SSRIs, MAO inhibitors, and many more) should always be on the consumption of Refrained from alcohol become. Especially when combining alcohol with tricyclic antidepressants or MAO inhibitors were partly life-threatening side effects described.

More information can be found here: Antidepressants and alcohol

The bulk of antidepressants are used in the Metabolized liver. Both activation and degradation are carried out by liver enzymes. This places a heavy burden on the liver in its function. Since alcohol is also metabolized via the liver, considerable interactions can occur. Both the effects of alcohol and antidepressants can be massively influenced. The described side effects of the antidepressants can be massively increased and sometimes become life-threatening. Depending on the preparation, a wide range of side effects can occur and all organs can be affected in their function. One strong reduced breathing, severe cardiac arrhythmia and impaired consciousness are possible. Also was of possible Personality changes reported. The known side effects of alcohol consumption (dizziness, nausea, insecurity of movement) can possibly increase to such an extent that an unconsciousness or even a coma is possible.

You might also be interested in the following articles: Amitriptyline and alcohol, Citalopram and alcohol

Side effects in sexuality

Another common side effect is sexual disorders. Especially when treated with SSRIs (citalopram, Fluoxetine, Paroxetine, sertraline) is often used by sexual dysfunction and a loss of libido (sexual desire) reported. The exact causes have not yet been clarified. The effects of altered serotonin levels in the central nervous system on the sexual organs are discussed.

The side effects in sexuality occur during therapy with SSRIs more common in men on. Nonetheless, women can also be affected. Frequently, patients report constant sexual aversion, difficulty producing or maintaining an erection or sexual arousal, and weak or absent orgasms.

Sexual dysfunction can also occur during therapy with tricyclic antidepressants. However, these are much rarer than with SSRIs. Patients also report regular sexual aversion and a possible reduction in potency.

Weight gain as a side effect

Many of the commonly prescribed antidepressants have an effect on the patient's weight. Depending on the patient, there is one Weight gain the risk of worsening depression. While many antidepressants lead to weight gain, there are also some preparations that are weight-neutral or even aimed at weight loss.

Tricyclic antidepressants (especially Amitriptyline) lead to weight gain via an increase in appetite. Depending on the patient, this can be up to several kilograms per month. In addition, the strong sleep-inducing antidepressant also leads Mirtazapine to an increase in weight.

When treating with single SSRIs (especially Fluoxetine) as well as bupropion and reboxetine, studies have shown a decrease in weight. This effect can be attributed to a generally reduced appetite, especially with high-dose therapy. At the same time, the occurring during treatment Dry mouth and change in taste lead to an increase in anorexia.

Numerous other antidepressants (including duloxetine, MAO inhibitors, other SSRIs) are usually weight-neutral and have no significant influence on appetite.

Duration of side effects

In general, the side effects of antidepressants occur primarily at the beginning of therapy. Instead, the desired antidepressant effect is delayed after a few weeks, which increases the risk of premature discontinuation of therapy. However, one should take into account that the side effects are largely in the course of antidepressant therapy continuously decrease or can be reduced by an accompanying medication. At the same time, there are great differences between the individual patients in terms of the occurrence and duration of side effects.

Symptoms that may typically occur throughout antidepressant treatment include sexual dysfunction, weight changes, and increases in intraocular pressure. Instead, the tremors that occurred at the beginning of the therapy, constant tiredness, sleep disorders and gastrointestinal complaints usually leave within a few weeks continuously.