As a selective serotonin re-uptake inhibitor or SSRI drug, the mechanism of action of fluoxetine is by increasing the level of serotonin in the brain. It has been suggested that patients with depression have lower levels of serotonin in their brain. Fluoxetine eases the symptoms of depression by treating this serotonin imbalance in the brain.



Serotonin is one of the neurotransmitters present in the brain which is easily reabsorbed once it is released. The mechanism of action of fluoxetine is to inhibit or slow down the metabolism of this neurotransmitter in order for the brain to have higher levels of serotonin. Patients with increased levels of serotonin were found to usually recover from their symptoms.

SSRI drugs like fluoxetine have been found to also help in the growth of new neurons, commonly called nerve cells, in patients. Neurons are very essential in facilitating information in the brain. It has been suggested that growth of new neurons allows the brain to have more room for processing new thoughts, memory, emotions, and motivations. Fluoxetine and other serotonin inhibitors hastens the growth of new nerve cells in the part of the brain responsible for improving the moods of the patients.

Since it often takes a longer time to treat the symptoms of depression, increasing fluoxetine doses is usually done. Doctors usually start a patient's medication on a lower dose before gradually increasing fluoxetine doses as the symptoms react on the drug. Improvement and prevention of a possible relapse of depression are the usual effects of increasing fluoxetine doses in patients.

Patients should not be alarmed that toxic effects from increasing fluoxetine levels may arise once their doctor suggests a higher dose. SSRI drugs are considered one of the safest antidepressant drugs that also cause the least number of side effects. Although SSRI drugs treat depression in the same manner, their side effects may vary in different patients. Possible side effects like nausea, diarrhea, headache, lack of sexual drive, drowsiness, and insomnia may be experienced but this depends in every patient. Some patients may have these side effects while others may not. These side effects can also diminish as the doctor adjusts the fluoxetine dose prescribed.

Increasing the level of fluoxetine dose to be taken is just normal in long-term medications and it doesn't mean that doctors will always increase the patients' dose. It is only done as the symptoms progress. This increases the patients chance of recovery and reduces the risk that the symptoms may come back once the medication is complete. Once the symptoms of depression diminish, doctors can start to decrease the fluoxetine dose to be taken. In this way, withdrawal symptoms from suddenly stopping the medication can be prevented. The dose may be decreased gradually every 2 weeks until the patient no longer has to take any dose.

Fluoxetine is one of the dependable drugs for the treatment of depression. It is important that patients understand that increasing fluoxetine doses is not intended to cause them any harm and that it is just a normal part of their treatment. It is one way of improving the drug's efficacy in treating depression.