Drug Warnings: Before taking Qvatic SR (quetiapine fumarate), inform your doctor if you have heart disease or a family history of long QT or sudden cardiac death, low blood pressure or a tendency to faint, diabetes or high cholesterol/triglycerides, liver disease, seizure disorders, glaucoma or urinary retention, thyroid problems, cataracts, or a history of depression or suicidal thoughts. Use in elderly patients with dementia-related psychosis is associated with increased mortality and stroke risk and is generally not approved—follow your clinician’s guidance closely. Avoid taking Qvatic SR with other sedating medicines unless advised, as combined effects can impair alertness and coordination.
Drug–Drug Interactions: Quetiapine is metabolized primarily by CYP3A4. Strong CYP3A4 inhibitors for example ketoconazole, itraconazole, clarithromycin, certain HIV protease inhibitors and grapefruit products can markedly raise blood levels; your prescriber may avoid these or lower your dose. Strong CYP3A4 inducers such as carbamazepine, phenytoin and rifampicin can lower quetiapine levels and reduce efficacy; your doctor may switch interacting drugs or adjust your dose. Additive sedation occurs with alcohol, benzodiazepines, opioids, sedating antihistamines, sleep medicines and some antipsychotics. Use caution with medicines that prolong the QT interval (certain antiarrhythmics, macrolides, fluoroquinolones and others) and with antihypertensives, which may enhance postural dizziness.
Drug–Food Interactions: Take Qvatic SR consistently as directed; your doctor may prefer evening dosing with a light meal. Avoid grapefruit or grapefruit juice, which can increase quetiapine exposure. Limit alcohol, as it increases sleepiness and slows reaction time.
Drug–Disease Interactions: Patients with liver impairment require lower starting doses and careful titration. Those with diabetes/metabolic syndrome need regular monitoring of weight, fasting glucose and lipids. People with heart-rhythm abnormalities, seizures, glaucoma or prostate enlargement, or severe constipation should discuss risks and monitoring plans with their clinician. Always share your full medical history to ensure safe and effective use of Qvatic SR 50/100/200/300/400 mg (quetiapine fumarate sustained-release).