Paroxetine is a prescription antidepressant medication. It belongs to a class of drugs known as selective serotonin reuptake inhibitors (SSRIs). Available under brand names including Paxil, it functions by increasing the levels of serotonin in the brain, a substance that helps maintain mental balance. This medication is formulated for oral administration. It is absorbed through the gastrointestinal tract and undergoes extensive metabolism in the liver.
Standard Dosing by Condition
For individuals with Major Depressive Disorder (MDD), treatment with paroxetine typically begins with a 20 mg dose taken once per day. Physicians may choose to increase the dosage in 10 mg increments at weekly intervals if the initial response is not sufficient. The usual therapeutic dose that is effective for most people falls within the 20 to 50 mg per day range. The maximum recommended daily dose for MDD is 50 mg.
The approach for Panic Disorder often starts with a lower dose to minimize potential initial anxiety. A starting dose of 10 mg per day is common. This dose is then gradually increased by 10 mg each week, based on the patient’s response and tolerance to the medication. The target effective dose for panic disorder is typically 40 mg per day, with a maximum limit of 60 mg daily.
In the case of Obsessive-Compulsive Disorder (OCD), the initial dose is generally 20 mg per day. The dose can be raised weekly in 10 mg increments to reach a therapeutic level. The recommended daily dose for OCD is 40 mg, though some individuals may require up to 60 mg per day for an optimal response. The maximum dose should not exceed 60 mg daily.
For those diagnosed with Social Anxiety Disorder, the standard starting dose is 20 mg once a day. If needed, this can be increased by 10 mg at weekly intervals. The effective dose range for social anxiety disorder is between 20 mg and 60 mg per day. The maximum daily intake is set at 60 mg.
Paroxetine Formulations and How to Take Them
Paroxetine is available in two main oral formulations: immediate-release (IR) and controlled-release (CR). The immediate-release version, which comes in tablet and liquid suspension form, releases the medication into the body shortly after being ingested. The controlled-release tablet, sold as Paxil CR, is designed with a special coating that allows the drug to be absorbed more slowly over several hours. This slower release mechanism can help reduce the likelihood of nausea for some individuals.
Immediate-release tablets are available in strengths of 10 mg, 20 mg, 30 mg, and 40 mg. Controlled-release tablets come in 12.5 mg, 25 mg, and 37.5 mg strengths. The medication is usually taken once daily, often in the morning, to prevent potential sleep disturbances. Taking the dose with food may help to prevent an upset stomach.
Controlled-release tablets must be swallowed whole and not be crushed, split, or chewed. Breaking the tablet would disrupt the slow-release coating, causing the full dose to be released at once. This could increase the risk of side effects.
Dose Modifications for Specific Groups
Dosing for elderly patients often requires a more cautious approach. Due to age-related changes in metabolism, older individuals may process paroxetine more slowly. The recommended starting dose for this group is typically lower, often 10 mg per day for immediate-release tablets. The maximum daily dose is also reduced, generally not exceeding 40 mg per day.
Patients with severe kidney or liver impairment also need dose adjustments. These conditions can significantly reduce the body’s ability to clear the medication, leading to higher concentrations of the drug in the bloodstream. For these individuals, the starting dose is usually 10 mg per day. The maximum recommended dose is typically limited to 40 mg daily to prevent accumulation and potential toxicity.
Managing Dose Changes and Discontinuation
Stopping paroxetine requires careful management to avoid adverse effects. Abruptly ceasing the medication is not recommended, as it can lead to a condition known as SSRI discontinuation syndrome. This syndrome occurs because the brain has adapted to the presence of the drug, and a sudden stop disrupts neurotransmitter balance.
To prevent this, a process of tapering is used. Tapering involves a gradual reduction of the dose over a period of several weeks or even months under the guidance of a doctor. The specific tapering schedule can vary widely depending on the individual, the dose they were taking, and how long they were on the medication. Common symptoms of discontinuation syndrome include:
- Dizziness
- Nausea
- Headache
- Anxiety
- Sensory disturbances often described as “brain zaps”