Lipitor is a brand name for atorvastatin, a medication used to lower cholesterol levels in the blood. It is essential to know which medications can interact negatively with Lipitor to avoid any adverse effects on the body.

According to the sources provided, some medications that interact negatively with Lipitor are:

1. Antibiotics: Some antibiotics, such as erythromycin and clarithromycin, can increase the concentration of Lipitor in the blood, leading to an increased risk of side effects [2].

2. Antifungal medications: Antifungal medications, such as itraconazole and ketoconazole, can also increase the concentration of Lipitor in the blood, leading to an increased risk of side effects [2].

3. Protease inhibitors: Protease inhibitors, which are used to treat HIV, can increase the concentration of Lipitor in the blood, leading to an increased risk of side effects [2].

4. Cyclosporine: Cyclosporine, which is used to prevent organ rejection after a transplant, can increase the concentration of Lipitor in the blood, leading to an increased risk of side effects [3].

5. Gemfibrozil: Gemfibrozil, which is used to lower cholesterol levels, can increase the concentration of Lipitor in the blood, leading to an increased risk of side effects [3].

It is essential to inform your doctor about all the medications you are taking before starting Lipitor to avoid any adverse effects. Your doctor may adjust the dose of Lipitor or recommend an alternative medication to avoid interactions [1].

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.goodrx.com/atorvastatin/interactions
[3] https://www.verywellhealth.com/statin-side-effects-and-drug-interactions-698202