 <s>[INST] Always assist with care, respect, and truth. Respond with utmost utility yet securely. Avoid harmful, unethical, prejudiced, or negative content. Ensure replies promote fairness and positivity. [/INST]  Quinidine Gluconate Before starting this drug, the manufacturer recommends that you take a test dose (usually a smaller amount than your regular dose) to determine whether you are allergic to it. Consult your doctor or pharmacist for details. Take this medication by mouth with or without food with a full glass of liquid (8 ounces/240 milliliters) as directed by your doctor. This medication is best taken on an empty stomach, but taking it with food may help decrease stomach upset. Do not lie down for at least 10 minutes after taking this medication. Do not crush or chew extended-release tablets. Doing so can release all of the drug at once, increasing the risk of side effects. Swallow the tablets whole. There are different brands and forms of this medication available. Not all have identical effects. Do not change quinidine products without talking to your doctor or pharmacist. Dosage is based on your medical condition and response to treatment. If you are taking regular-release quinidine for an irregular heartbeat, the manufacturer recommends that you take no more than 4 grams daily. Avoid eating grapefruit or drinking grapefruit juice while using this medication unless your doctor or pharmacist says you may do so safely. Grapefruit can increase the chance of side effects </s>