What is the difference between quetiapine fumarate and quetiapine

They will examine your eyes when you start treatment and every 6 months during treatment. For people with seizures: Seizures have occurred in patients with or without epilepsy while taking quetiapine. Quetiapine may make it harder to control seizures in people with epilepsy.

Your doctor should monitor you for an increase in seizures while taking this drug. For people with hypothyroidism low thyroid level : Quetiapine may lower thyroid hormone levels and worsen your existing condition.

Your doctor should monitor your blood thyroid hormone levels before and during treatment with this drug. For people with heart problems: Ask your doctor if this drug is safe for you. This drug increases the risk of abnormal heart rhythms. For people with liver problems: Quetiapine is mainly broken down in the body by the liver.

As a result, people with liver problems may have increased blood levels of this drug. This raises the risk of side effects from this drug. For people with severe constipation : Quetiapine can cause constipation and increase your risk of gastrointestinal problems including bowel block.

This has been deadly in people taking this drug with other drugs that slow movement through your gastrointestinal tract. If you have questions, talk with your doctor.

Using quetiapine with anticholinergic drugs may increase the risk of gastrointestinal problems. For pregnant women: Quetiapine is a category C pregnancy drug. That means two things:. This drug should only be used if the potential benefit justifies the potential risk.

For women who are breastfeeding: Quetiapine may pass into breast milk and may cause side effects in a child who is breastfed. Talk to your doctor if you breastfeed your child. You may need to decide whether to stop breastfeeding or stop taking this medication. For seniors: The kidneys and livers of older adults may not work as well as they used to. This can cause your body to process drugs more slowly.

As a result, a higher amount of a drug stays in your body for a longer time. This raises your risk of side effects. All possible dosages and drug forms may not be included here. Your dosage, drug form, and how often you take the drug will depend on:. Your doctor may start you on a lowered dosage or a different dosing schedule. This can help keep levels of this drug from building up too much in your body. Your doctor may start you at a dosage of 50 mg daily. They may later increase it, adding 50 mg to your daily dose.

The dosage may be increased at a slower rate, and a lower total daily dose may be used to lessen the risk of side effects. It has not been confirmed that quetiapine is safe and effective to use for this purpose in children younger than 13 years. This medication has not been studied in children to use for this purpose. It should not be used in children younger than 18 years.

Your doctor may start you on a lowered dose or a different dosing schedule. The dosage will then need to be increased according to the dosage schedule from when you first started the medication. However, because drugs affect each person differently, we cannot guarantee that this list includes all possible dosages.

Always speak with your doctor or pharmacist about dosages that are right for you. Quetiapine oral tablet is used for long-term treatment. If you stop taking quetiapine suddenly, you may also have trouble sleeping or trouble staying asleep, or have nausea or vomiting. For this drug to work well, a certain amount needs to be in your body at all times.

If you take too much: You could have dangerous levels of the drug in your body. Symptoms of an overdose of this drug can include:. But if your symptoms are severe, call or go to the nearest emergency room right away. What to do if you miss a dose: Take your dose as soon as you remember. But if you remember just a few hours before your next scheduled dose, take only one dose.

Never try to catch up by taking two doses at once. This could result in dangerous side effects. A prescription for this medication is refillable. You should not need a new prescription for this medication to be refilled. Your doctor will write the number of refills authorized on your prescription. Quetiapine can make your body less able to manage your temperature. This can cause your temperature to increase too much, leading to a condition called hyperthermia. Symptoms can include hot skin, excessive sweating, fast heartbeat, rapid breathing, and even seizures.

To help prevent this, do the following during your treatment with this drug:. You and your doctor should monitor certain health issues. This can help make sure you stay safe while taking this drug. Read our disclaimer for details. Last Update Posted : July 16, Study Description. This study will compare the tolerability of Quetiapine Fumarate immediate release formulation and Quetiapine Fumarate extended release formulation during initial dose escalation in healthy volunteers.

FDA Resources. Arms and Interventions. Outcome Measures. Eligibility Criteria. Information from the National Library of Medicine Choosing to participate in a study is an important personal decision.

Inclusion Criteria: Provision of informed consent prior to any study specific procedures Weight of at least 50 kg Exclusion Criteria: A history or presence of neurological, hematological, psychiatric, gastrointestinal, hepatic, pulmonary, or renal disease or other conditions known to interfere with the absorption, distribution, metabolism, or excretion of drugs Positive test results for alcohol or drugs of abuse Positive test results for human immunodeficiency virus HIV , hepatitis B surface antigen HBsAg , or hepatitis C antibody.

Contacts and Locations. Information from the National Library of Medicine To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor. Please refer to this study by its ClinicalTrials. More Information. Patients on quetiapine XR had a numerically longer duration of hospitalization than those in the quetiapine IR group Patient comorbidities and reasons for treatment were recorded for psychiatric conditions other than schizophrenia, as well as for somatic reasons.

There were a number of reasons for treating other disorders, including insomnia, psychosis, anxiety, and schizophrenia per se. There was no significant difference between the groups with respect to insomnia or sedation as reasons for treatment. A total of 33 patients used both quetiapine XR and quetiapine IR during hospitalization. Four were taking both quetiapine XR and IR when admitted to the hospital, 18 Among the 18 patients who used both quetiapine formulations in combination, 14 patients used a higher mean dose of quetiapine XR Table 5.

This naturalistic study investigated the clinical use of quetiapine XR and quetiapine IR in hospitalized patients with schizophrenia in 14 psychiatric clinics in Sweden. The primary finding was that quetiapine XR was used in considerably higher doses than quetiapine IR. This finding supports the interpretation that quetiapine XR more often is used as the main antipsychotic drug, whereas quetiapine IR is more often used as an add-on medication in schizophrenia.

Overall, patients had two or more — and in some cases up to seven or eight — antipsychotic medications during hospitalization, reflecting the typical situation faced by physicians of severely ill patients. The most common historical combination of medications in this setting is that of a typical plus an atypical antipsychotic [ Bingefors et al.

This was also the case here, the most common typical antipsychotics being zuclopenthixol and haloperidol when used for at least 7 days. Patients with comorbid substance abuse were significantly more likely to receive treatment with quetiapine XR than IR. Also, patients treated with quetiapine XR were reported to have more somatic disease than those on quetiapine IR.

Further, significant differences in the reported reasons for treatment between quetiapine XR and IR were seen. Patients on quetiapine XR were more often treated for schizophrenia per se and those on quetiapine IR more often for psychosis, although this result should be interpreted with caution as reported reasons for treatment may not be consistent across prescribers and patients. Further, although statistically not significant, lower GAF scores at hospital admission, longer duration of hospitalization, and higher use of ECT was reported for patients receiving quetiapine XR compared with IR.

Taken together, the present study points to a different use of quetiapine XR compared with quetiapine IR in this setting. Medication adherence should arguably increase in importance with disease severity. In fact, adherence is a considerable challenge in schizophrenia [ Goff et al.

However, any improvement in adherence will improve patient outcomes [ Ascher-Svanum et al. A complex dosing regimen is one factor that may have a considerable negative impact on drug adherence. Once daily dosing has been shown to be significantly associated with improved adherence in patients with schizophrenia, also when controlling for various covariates [ Remington et al. In this study, patients receiving quetiapine IR twice daily dosing reported nonadherence as a reason for discontinuation of treatment significantly more often than those on quetiapine XR once daily dosing.

Of these patients, 18 used both formulations concomitantly. Although polypharmacy is common among these patients, it does not in itself explain why quetiapine XR and IR are used simultaneously, but may indicate that quetiapine XR and IR are sometimes used in a complementary as opposed to a substitutional fashion.

That interpretation is further supported by the fact that 14 out of these 18 patients used quetiapine XR in considerably higher doses than IR. Clearly, quetiapine IR is more often used as an add-on medication in these patients, potentially for its sedative effect. One may also notice that, in the patients who used quetiapine XR and IR sequentially, switches from quetiapine IR to XR were far more common than switches in the other direction. A differential use of the two formulations of quetiapine in clinical practice of schizophrenia may be explained by their different pharmacological properties.

Quetiapine XR, with its smoother plasma concentration profile than quetiapine IR allowing for faster titration [ Figueroa et al. A recent study investigated if the pharmacokinetic differences translate into different time curves for central D 2 dopamine receptor occupancy.

Peak D 2 receptor occupancy was significantly higher with the IR formulation than quetiapine XR and may explain pharmacodynamic differences [ Nord et al.

A divergence in receptor occupancy between the quetiapine formulations may be expected to translate to some differences in clinical effects. In fact, quetiapine XR has been associated with a lower intensity of self-reported sedation than quetiapine IR [ Datto et al.

This study has important strengths. First, our naturalistic study avoided the highly selected patient populations and arguably unrealistic setting of RCTs by enrolling schizophrenia inpatients faced by psychiatrists in their everyday clinical practice. Clinical practice differs substantially from the context of RCTs in terms of characteristics of patients e. Second, there was no bias in patient selection also due to the fact that informed consent was not required.

Third, a retrospective data analysis of medical records ensured that treatment choice for patients was not influenced and thus real-life clinical data were collected.

Fourth, patients from 14 geographically spread out psychiatric clinics participated in the study and therefore the results should be representative for Sweden. There are also some limitations. First, the results build on reports by the healthcare professionals and may not be fully accurate. Second, this study enrolled severely ill, hospitalized patients with schizophrenia and so the results may not be applicable to the outpatient clinical setting.

Further, this study is limited to Swedish psychiatric inpatient care.