Venlafaxine: What Is it and What Is it Used For?

All psychotropic drugs alter the concentration or effect of neurotransmitters in the body. Venlafaxine prolongs the action of serotonin and norepinephrine, which helps treat depression.

Antidepressants are a group of drugs used to treat depression and other psychiatric illnesses. They produce their pharmacological effect by intervening in the action of various neurotransmitters. One of these drugs is venlafaxine, but what is it and what is it used for?

In general terms, depression is a pathology that has multiple symptoms, however, it’s characterized by apathy and lack of motivation when carrying out pleasant activities. The disease can affect any individual, although studies show that over 64 percent of diagnosed patients are women.

The treatment of depression is based on the combination of psychological therapy and the intake of drugs. Therefore, there are a large number of different compounds that can help to improve the symptoms presented. All compounds of this nature have a delayed effect, and so they should be consumed for a long period of time.

What is venlafaxine?

The drug in question is an antidepressant belonging to the group of dual serotonin and norepinephrine reuptake inhibitors. Therefore, venlafaxine works by prolonging the effect that these substances have on the body.

The form of administration of the drug is orally and is available in immediate-release tablet and prolonged-release tablet presentations. The dosage can also vary, and you can find the compound in 37.5 milligram, 75 milligram, and 150-milligram formats of the active principle.

The drug in question has good intestinal absorption, and it isn’t affected by the intake of food and beverages. However, you’ll need to be alert to its consumption by patients with liver failure, since this organ won’t be able to process all the medicine properly.

There are several commercial preparations of venlafaxine.
This drug is only available for oral consumption.

The drug’s mechanism of action

Before talking about the drug’s mechanism of action, it’s necessary to talk a little about the relationship between serotonin and depression. The neurotransmitter in question influences the brain centers that regulate mood stability, so increasing its concentration helps reduce the impact of psychiatric pathologies.

Serotonin is secreted by a set of neurons in a histological area called the synaptic cleft. Once released, this substance will come into contact with receptors located on the membrane of another neuron.

After a certain time, the serotonin will be taken up by the initial neuron again, thus decreasing its concentration in the cleft.

The active metabolite of the drug, O-desmethylvenlafaxine is involved in the serotonin reuptake process. The compound will be responsible for blocking the SERT receptor, which is responsible for capturing the neurotransmitter. In this way, serotonin levels will remain high in the brain.

On the other hand, the drug is also capable of inhibiting norepinephrine reuptake by blocking NAT transporters. This effect is important because various studies demonstrate the role of this neurotransmitter in the pathogenesis and treatment of depression.

What’s venlafaxine used for?

As mentioned before, this drug is used to treat depression in adults. However, it’s also useful in the treatment of other common psychiatric illnesses such as anxiety. This pathology is characterized by excessive concern in situations that are considered to be normal.

In this sense, both slow-release and quick-release tablets are very useful in alleviating the symptoms experienced. In addition, the drug is also useful in treating the following conditions:

The great importance of this type of drug lies in the fact that it is necessary in order to solve the medical condition in question.

The disease can be impossible to control if antidepressant drugs aren’t used.

How should it be taken?

Specific instructions for taking venlafaxine should always be provided by the treating physician. According to the internal package insert of the drug, the recommended starting dose is 75 milligrams per day, however, the starting dose will be 37.5 milligrams in patients with panic attacks.

This drug is well tolerated by the body, so a person can consume a maximum dose of up to 375 milligrams per day, divided into 3 or 4 doses. In some cases, the specialist may increase the initial dose of the drug gradually, however, the increase should be done only once a week.

The tablets should be taken every day, around the same time and preferably with food. Venlafaxine is an oral drug that must be swallowed whole, therefore the tablets shouldn’t be cut or crushed.

Suspension of treatment should only be carried out under medical supervision in order to avoid the appearance of collateral effects. It’s important to decrease the dose progressively before stopping treatment.

Venlafaxine side effects

As with all commercialized drugs, the compound in question has a certain degree of toxicity, which is why adverse effects may appear. However, the symptoms presented don’t usually limit daily activities and tend to disappear after a few days.

The safety of venlafaxine is supported by several studies in which only 6.4% of treated people experienced side effects. Among the most frequent symptoms associated with the consumption of this drug, the following stand out:

  • Dizziness
  • Headache
  • Sickness
  • Dry mouth.
  • Day and night sweating
Venlafaxine causes gastrointestinal upset relatively frequently.
Nonspecific gastrointestinal manifestations are common during venlafaxine consumption.

Precautions and contraindications

The main contraindication for the consumption of this medicine is the presence of an allergy to the active principle or to any of its excipients. In addition, venlafaxine should also not be ingested if any drug belonging to the MAOIs (a different group of antidepressants) has been taken in the last 14 days.

On the other hand, this compound shouldn’t be administered to people under 18 years of age, and so it isn’t useful in the treatment of childhood anxiety. This is because children are more likely to develop side effects, most notably suicidal thoughts.

Pregnant women should be very careful with the consumption of this medicine. Venlafaxine should only be prescribed by a physician when the benefits of its use outweigh the risks. The drug is able to cross the placental barrier and affect the baby, in addition, it increases the risk of vaginal bleeding if it’s consumed in the last trimester of pregnancy.

There are also some situations that should be notified to the specialist before starting treatment, among which the following stand out:

  • Consumption of other medications
  • Presence of liver or kidney disease
  • Eye problems, such as glaucoma
  • History of cardiovascular disorders, seizures, aggression, or bipolar disorder

A safe drug with few side effects

Venlafaxine is a very useful drug in the treatment of major depressive disorder and other psychiatric conditions. This drug increases the concentration of serotonin and norepinephrine in the brain, two neurotransmitters that intervene in the balance of the mood, improving the symptoms of depression.

The drug in question should only be ingested under a medical prescription and following the instructions given by the specialist. Uncontrolled consumption of the compound can lead to severe side effects.

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