Fortamet

Fortamet is a prescription medication used to treat type 2 diabetes. Fortamet belongs to a group of drugs called biguanides, which work by helping your body respond better to the insulin it makes naturally, decreasing the amount of sugar your liver makes, and decreasing the amount of sugar your intestines absorb.

This medication comes in an extended-release tablet. It is typically taken once a day. Swallow Fortamet extended-release tablets whole.

Common side effects of Fortamet include diarrhea, nausea, and upset stomach.

Fortamet is a prescription medication used to treat type 2 diabetes.

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Take Fortamet exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.

For the extended release form, Fortamet, the starting dose is 500 mg once daily, and the maximum dosing is 2000 mg once daily (or 1000 mg twice daily).

The maximum total daily dose of Fortamet for people taking insulin is 2000 mg.

WARNINGS

Lactic Acidosis:

Lactic acidosis is a rare, but serious, metabolic complication that can occur due to metformin accumulation during treatment with Fortamet; when it occurs, it is fatal in approximately 50% of cases. Lactic acidosis may also occur in association with a number of pathophysiologic conditions, including diabetes mellitus, and whenever there is significant tissue hypoperfusion and hypoxemia. Lactic acidosis is characterized by elevated blood lactate levels (>5 mmol/ L), decreased blood pH, electrolyte disturbances with an increased anion gap, and an increased lactate/pyruvate ratio. When Fortamet is implicated as the cause of lactic acidosis, Fortamet plasma levels >5 μg/mL are generally found.

A small number of people who have taken Fortamet have developed a serious condition called lactic acidosis. Lactic acidosis is caused by a buildup of lactic acid in the blood. This happens more often in people with kidney problems. Most people with kidney problems should not take Fortamet. See "Side Effects".

Some conditions increase your chance of getting lactic acidosis, or cause other problems if you take Fortamet. Most of the conditions listed below can increase your chance of getting lactic acidosis.

Do not take Fortamet if you:

• have kidney problems
• have liver problems
• have heart failure that is treated with medicines, such as Lanoxin (digoxin) or Lasix (furosemide)
• drink a lot of alcohol. This means you binge drink for short periods or drink all the time.
• are seriously dehydrated (have lost a lot of water from your body)
• are going to have an x-ray procedure with injection of dyes (contrast agents)
• are going to have surgery
• develop a serious condition, such as heart attack, severe infection, or a stroke
• are 80 years or older and you have NOT had your kidney function tested

Do not drink a lot of alcohol drinks while taking this medication. This means you should not binge drink for short periods, and you should not drink a lot of alcohol on a regular basis. Alcohol can increase the chance of getting lactic acidosis.

Serious side effects have been reported including:

Lactic Acidosis. In rare cases, Fortamet can cause a serious side effect called lactic acidosis. This is caused by a buildup of lactic acid in your blood. This build-up can cause serious damage. Lactic acidosis caused by Fortamet is rare and has occurred mostly in people whose kidneys were not working normally. Lactic acidosis has been reported in about one in 33,000 patients taking metformin over the course of a year. Although rare, if lactic acidosis does occur, it can be fatal in up to half the people who develop it.

It is also important for your liver to be working normally when you take Fortamet. Your liver helps remove lactic acid from your blood.

Make sure you tell your doctor before you use Fortamet if you have kidney or liver problems. You should also stop using Fortamet and call your doctor right away if you have signs of lactic acidosis. Lactic acidosis is a medical emergency that must be treated in a hospital.

Signs of lactic acidosis:

• feeling very weak, tired, or uncomfortable
• unusual muscle pain
• trouble breathing
• unusual or unexpected stomach discomfort
• feeling cold
• feeling dizzy or lightheaded
• suddenly developing a slow or irregular heartbeat

If your medical condition suddenly changes, stop taking metformin and call your doctor right away. This may be a sign of lactic acidosis or another serious side effect.

Common side effects of Fortamet include:

• diarrhea
• nausea
• upset stomach

These side effects generally go away after you take the medicine for a while. Taking your medicine with meals can help reduce these side effects. Tell your doctor if the side effects bother you a lot, last for more than a few weeks, come back after they've gone away, or start later in therapy. You may need a lower dose or need to stop taking the medicine for a short period or for good.

About 3 out of every 100 people who take Fortamet have an unpleasant metallic taste when they start taking the medicine. It lasts for a short time.

Fortamet rarely causes hypoglycemia (low blood sugar). However, hypoglycemia can happen if you do not eat enough, if you drink alcohol, or if you take other medicines to lower blood sugar.

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:

• beta-blockers
• cough and cold products containing decongestants
• calcium channel blockers
• cimetidine (Tagamet)
• corticosteroids
• digoxin (Lanoxin)
• diuretics such as furosemide (Lasix)
• estrogens
• insulins or other medicines for diabetes
• isoniazid (INH, Nydrazid)
• morphine
• niacin (nicotinic acid, Niaspan)
• nifedipine
• oral contraceptives
• oral steroids
• phenothiazines such as promethazine (Phenergan)
• phenytoin (Dilantin)
• procainamide
• quinidine
• quinine
• ranitidine
• thyroid medicines such as levothyroxine (Levothroid, Levoxyl, Synthroid, Tirosint)
• triamterene
• trimethoprim
• vancomycin

This is not a complete list of Fortamet drug interactions. Ask your doctor or pharmacist for more information.

Tell your doctor if you are pregnant or plan to become pregnant. It is not known if Fortamet will harm your unborn baby.

Tell your doctor if you are breastfeeding or plan to breastfeed. It is not known if Fortamet is excreted in human breastmilk or if it will harm your nursing baby.

Upset stomach and diarrhea are common metformin side effects. They usually go away after a short while. Talk to your doctor if it continues for more than a few weeks.

Avoid drinking large amounts of alcohol. Taking metformin with alcohol can affect blood sugar control.

A small percentage of people taking metformin will develop a buildup of lactic acid in the blood, known as lactic acidosis. This happens more often in people with kidney problems.