Grasp the precautions about Atorvastatin calcium.😎😎😎

Atorvastatin calcium is a commonly used statin lipid-lowering drug. Indications are patients with hypercholesterolemia and primary hypercholesterolemia. It is including patients with familial hypercholesterolemia or mixed hyperlipidemia. If diet therapy and other non-drug treatments are not satisfactory, it can be used to treat elevated total cholesterol (TC), elevated low-density lipoprotein cholesterol (LDL-C), elevated apolipoprotein B and triglyceride (TG) increased.

1. Dosage

The usual starting dose is 10 mg once a day and adjust the dose every 4 weeks or longer. The maximum dose is 80 mg once a day.

• It takes at least 4 weeks for statins to achieve the maximum lipid-lowering effect, so the interval between dose adjustments should be 4 weeks or longer.
• Atorvastatin calcium contains very little amount of calcium which does not affect calcium supplementation.

Kidney disease: It neither affect the blood concentration nor affect its lipid-lowering effect. So there is no need to adjust the dose.

• Patients with active liver disease, pregnant women or women of childbearing age who may conceive are prohibited.

Elderly patients (≥65 years old): The blood concentration is about 40% higher than young people. Any dose of atorvastatin can lower low-density lipoprotein (LDL-C) significantly higher than young people.

• When using atorvastatin, the elderly need to pay special attention to adverse muscle reactions. When there is unexplained muscle weakness, muscle tenderness, muscle pain, neck pain, joint swelling, especially when it is accompanied by discomfort or fever, it is necessary to timely medical treatment.

2. Medication time

The half-life of atorvastatin is 14 hours. The half-life of active metabolites is 20-30 hours. The lipid-lowering effect of atorvastatin is mainly (about 70%) related to active metabolites. Compared with the morning administration, the blood concentration of the evening administration is reduced by about 30%. However, no matter when it is administered during the day, its cholesterol-lowering effect is the same.

• The daily dose of atorvastatin can be taken at any time during the day and is not affected by meals.
• The peak time of cholesterol synthesis is from 0:00 to 3:00 and other statins with shorter half-lives need to be taken before going to bed.

3. Lipid-lowering intensity

The lipid-lowering intensity of statins (including atorvastatin) is related to the dose. However, even if the dose is doubled, the lipid-lowering intensity only increases by about 6%.

• Statins can effectively reduce triglycerides. Patients with hypercholesterolemia and high triglycerides should first choose statin lipid-lowering drugs.

Dose-response relationship of Atorvastatin
	10mg	20mg	40mg	80mg
LDL-C	-39%	-43%	-50%	-60%
HDL-C	+6%	+9%	+6%	+5%
TG	-19%	-26%	-29%	-37%
TC	-29%	-33%	-37%	-45%

4. Interaction

Atorvastatin is metabolized by cytochrome CYP3A4. When combined with a strong CYP3A4 inhibitor, the blood concentration and bioavailability of atorvastatin increase.

Grapefruit juice: Avoid taking with grapefruit or grapefruit juice.

Gemfibrozil and Niacin: The risk of myopathy/rhabdomyolysis is increased, so avoid combined with gemfibrozil or niacin.

Combined with Clarithromycin: The initial dose of atorvastatin is 10 mg once a day. The maximum dose is 20 mg once a day.

Combined with Itraconazole: The initial dose of atorvastatin is 10 mg once a day. The maximum dose is 40 mg once a day.