Atorvastatin belongs to the group of medications known as HMG CoA reductase inhibitors ("statins") or lipid metabolism regulators. It is used to treat people who have high cholesterol levels, including people who have certain inherited cholesterol disorders. When you use this medication, you also need to make lifestyle changes, which may include switching to a diet low in fat and cholesterol, quitting smoking, and increasing the amount of exercise you do.

Atorvastatin works by blocking an enzyme that is used to make cholesterol in the liver. When that enzyme is blocked, less cholesterol is produced and the amount of cholesterol in the blood decreases. Atorvastatin lowers the level of total cholesterol and low-density lipoprotein (LDL, or "bad" cholesterol), and raises high-density lipoprotein (HDL, or "good" cholesterol) levels. Reduction of cholesterol levels in the blood has been shown to reduce the risks associated with heart disease, such as heart attack.

Atorvastatin is used to reduce the risk of heart attack for people experiencing symptoms associated with heart disease.

Atorvastatin is also used to reduce the risk of heart attack for people with high blood pressure who have at least 3 additional risk factors for heart disease but are not experiencing symptoms associated with heart disease. The risk factors of heart disease for these individuals include:

• being male
• being 55 years old or older
• enlarged heart ventricles
• family history of heart disease
• smoking
• specific abnormalities on an ECG
• a total cholesterol to HDL-cholesterol ratio of 6 or higher
• type 2 diabetes
• specific types of protein in the urine

Atorvastatin is also used to reduce the risk of heart attack and stroke for people with high blood pressure and type 2 diabetes who have other risk factors for heart disease but are not experiencing symptoms associated with heart disease. The risk factors of heart disease for these individuals include:

• a specific type of protein in the urine
• being 55 years old or older
• disease of the retina
• smoking

Atorvastatin may be used in addition to diet to reduce cholesterol for adolescents between 10 and 17 years of age with increased cholesterol levels and family history of early heart disease or 2 or more risk factors for cardiovascular disease.

The medication usually takes about 2 to 4 weeks to have a significant effect on the cholesterol level in your blood. After this time, your doctor will likely send you for a blood test to check for changes in your cholesterol levels.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

When you start taking atorvastatin, you should be on a cholesterol-lowering diet. If appropriate, a health care professional will discuss an individualized program of weight control and physical exercise with you.

The recommended starting dose of atorvastatin for adults is 10 mg or 20 mg daily, preferably in the evening, with or without food. Your doctor will do blood tests to tell how well this dose is working for you and may gradually increase the dose to get the desired response. The maximum recommended dose for adults is 80 mg taken once daily.

For children 10 to 17 years of age who are taking this medication to treat inherited cholesterol disorders, the recommended dose ranges from 10 mg to 20 mg daily. Doses greater than 20 mg have not been studied.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

For best results in lowering cholesterol, it is very important to closely follow the diet suggested by your doctor. It is also very important that atorvastatin be taken regularly and exactly as prescribed by your doctor.

If you miss a dose of this medication, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature and keep it out of the reach of children.

Do not take this medication if you:

• are allergic to atorvastatin or any ingredients of the medication
• are breast-feeding
• are pregnant or plan to become pregnant
• have active liver disease or unexplained increases in liver function tests
• are taking any of the following medications:
  • boceprevir
  • cyclosporine
  • elbasvir/grazoprevir
  • glecaprevir/pibrentasvir
  • ledipasvir/sofosbuvir
  • telaprevir
  • velpatasivr/sofosbuvir

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• diarrhea
• dizziness
• gas
• hair loss
• itchiness
• joint pain
• nausea
• nightmares
• rash
• sexual problems
• stomach pain
• trouble sleeping
• vomiting

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• breast enlargement (males)
• chest pain
• confusion
• cough, shortness of breath, fever
• increase in cold- or flu-like symptoms (e.g., sore throat, runny nose, nasal congestion, fatigue, headache)
• loss of sensation in part of body
• memory loss
• muscle aches
• signs of clotting problems (e.g., unusual nosebleeds, bruising, blood in urine, coughing blood, bleeding gums, cuts that don’t stop bleeding)
• signs of depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
• symptoms of high blood sugar (e.g., frequent urination, increased thirst, excessive eating, unexplained weight loss, poor wound healing, infections, fruity breath odour)
• symptoms of bone or soft tissue tumours in children (e.g., unusual pain, swelling, tenderness or lump, bone pain, unexplained bone fracture, fever, fatigue, weight loss)
• symptoms of liver damage (such as yellow skin or eyes, abdominal pain, dark urine, clay-coloured stools, loss of appetite, nausea and vomiting, or itching)
• symptoms of a ruptured tendon (e.g., popping or snapping sound when injury occurs, very painful lower leg, difficulty walking, swollen or bruised calf, inability to stand on toes of foot of injured leg)
• tingling or painful sensation in hands, arms, legs, or feet

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of pancreatitis (e.g., abdominal pain on the upper left side, back pain, nausea, fever, chills, rapid heartbeat, swollen abdomen)
• symptoms of muscle damage (unexplained muscle pain, tenderness or weakness, or brown or discoloured urine – especially if you also have a fever or a general feeling of being unwell)
• symptoms of a serious allergic reaction such as swelling of the face or throat, hives, or difficulty breathing

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Alcohol: People who drink large quantities of alcohol should be closely monitored by their doctor while they are taking this medication.

Cardiovascular: There is an increased risk of hemorrhagic stroke if atorvastatin is started within 6 months of having a stroke or transient ischemic attack (TIA). If you have a history of stroke or have had a recent stroke, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Diabetes: Atorvastatin may cause an increase in blood sugar levels and glucose tolerance may change. People with diabetes may find it necessary to monitor their blood sugar more frequently while using this medication.
If you have diabetes or are at risk for developing diabetes, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Diet: Atorvastatin is not intended to be used alone to reduce high cholesterol levels. It is important that a cholesterol-reducing diet along with appropriate exercise be attempted before taking any medication and continued while taking medication.

Grapefruit juice: Taking atorvastatin and consuming grapefruit juice may result in an increased amount of atorvastatin in the body, and lead to side effects. If you regularly drink grapefruit juice, talk to your doctor or pharmacist about whether you should change your diet.

Hypersensitivity reaction: A severe allergic reaction called hypersensitivity syndrome has been reported by some people using other medications in the same family as atorvastatin. Get immediate medical attention if you have symptoms of a severe allergic reaction, including fever, swollen glands, yellowing of the skin or eyes, or flu-like symptoms with skin rash or blistering.

Kidney function: If you have decreased kidney function or a history of kidney disease, you may be at an increased risk of developing muscle effects while taking atorvastatin. The lowest effective dose of atorvastatin should be used and your doctor should follow you closely. If you have kidney problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Liver function: Atorvastatin may reduce liver function and can cause liver failure, although this is rare. This medication should not be used by people with active liver disease or by people whose liver function tests are higher than normal. If you have liver problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. Your doctor may want to test your liver function regularly with blood tests while you are taking this medication.

If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.

Muscle effects: In rare cases, serious muscle pain, cramps, and weakness have been associated with the use of statin medications (i.e., cholesterol-lowering medications whose names end in "statin," such as atorvastatin, fluvastatin, lovastatin, pravastatin, rosuvastatin, or simvastatin), especially at higher doses. Before taking this medication, tell your doctor or pharmacist if you:

• have kidney or liver problems
• are taking niacin or a fibrate medication (such as gemfibrozil, fenofibrate)
• have an underactive thyroid gland (hypothyroidism)
• regularly drink more than 3 alcoholic drinks per day
• have had any past problems with muscles (pain, tenderness) after taking a statin such as atorvastatin, fluvastatin, lovastatin, pravastatin, rosuvastatin, or simvastatin
• have a personal or family history of inherited muscle problems
• are over 65 years old
• have undergone surgery or suffered any traumatic injury
• are frail
• do excessive physical exercise
• have diabetes
• are taking medications that may increase the amount of atorvastatin in the body or are taking other medications that can cause muscle damage

Report any unexplained muscle pain, tenderness, weakness, or cramps, or any brown or discoloured urine to your doctor immediately, particularly if you are also experiencing malaise (a general feeling of being unwell) or fever.

Pregnancy: Cholesterol is necessary for the development of an unborn baby. Taking atorvastatin during pregnancy reduces the amount of cholesterol reaching the developing baby and may cause harm to the baby. Atorvastatin should not be taken by pregnant people. If you become pregnant while taking this medication, stop taking it immediately and contact your doctor.

Breast-feeding: It is not known if atorvastatin passes into breast milk. If you are breast-feeding and taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: There is limited experience with the use of this medication by children. Atorvastatin has only been studied for use by children aged 10 to 17 years who have inherited cholesterol disorders (also known as familial hypercholesterolemia).

Seniors: If you are over 70 years old, you may experience more side effects. Your doctor will monitor you closely while you are taking this medication.

For a full list of interactions, use the Drug Interaction Checker available on the Drugs.com website.

If you are taking other medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.