Drug Interactions between metformin / saxagliptin and phenytoin

MetFORMIN should be taken with meals, and excessive alcohol intake (either short-term binge drinking or frequent consumption) should be avoided during treatment. Taking metFORMIN with alcohol may increase the risk of a rare but serious and potentially life-threatening condition known as lactic acidosis, which is a buildup of lactic acid in the blood that can occasionally occur during treatment with metformin-containing products. Lactic acidosis is more likely to occur if you have kidney or liver disease, acute or unstable congestive heart failure, or dehydration. You should seek immediate medical attention if you develop potential signs and symptoms of lactic acidosis such as fatigue, weakness, muscle pain, increasing drowsiness, abdominal pain or discomfort, slow or irregular heartbeat, breathing difficulty, chills, and other unusual symptoms. Alcohol may also affect blood glucose levels in patients with diabetes. Both hypoglycemia (low blood sugar) and hyperglycemia (high blood sugar) may occur, depending on how much and how often you drink. You should avoid using alcohol if your diabetes is not well controlled or if you have high triglycerides, neuropathy (nerve damage), or pancreatitis. Moderate alcohol consumption generally does not affect blood glucose levels if your diabetes is under control. However, you should limit your alcohol intake due to the risk of lactic acidosis with metformin. Avoid drinking alcohol on an empty stomach or following exercise, as it may increase the risk of hypoglycemia. Talk to your doctor or pharmacist if you have any questions or concerns about metformin.

Phenytoin levels may decrease when the suspension is given with enteral feedings. This could lead to a loss of seizure control. You could interrupt the feeding for 2 hours before and after the phenytoin dose. Alternatively, you may give the phenytoin suspension diluted in water and flush the tube with water after administration. These would make it easier for your body to absorb the medication. However, this still may not entirely avoid the interaction and may not always be feasible. You should have your phenytoin levels checked upon starting and stopping of enteral feedings. In addition, using phenytoin together with food may alter the effects of phenytoin. Contact your doctor if you experience worsening of seizure control or symptoms of toxicity, including twitching eye movements, slurred speech, loss of balance, tremor, muscle stiffness or weakness, nausea, vomiting, feeling light-headed, fainting, and slow or shallow breathing. If your doctor does prescribe these medications together, you may need a dose adjustment or special test to safely use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Ask your doctor before making any changes to your therapy.

Alcohol may affect blood glucose levels in patients with diabetes. Both hypoglycemia (low blood sugar) and hyperglycemia (high blood sugar) may occur, depending on how much and how often you drink. You should avoid using alcohol if your diabetes is not well controlled or if you have high triglycerides, neuropathy (nerve damage), or pancreatitis. Moderate alcohol consumption generally does not affect blood glucose levels if your diabetes is under control. However, it may be best to limit alcohol intake to one drink daily for women and two drinks daily for men (1 drink = 5 oz wine, 12 oz beer, or 1.5 oz distilled spirits) in conjunction with your normal meal plan. Avoid drinking alcohol on an empty stomach or following exercise, as it may increase the risk of hypoglycemia. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.