Here are 15 side effects and potential adverse effects of atorvastatin, including what they feel like, why they happen, how concerning they are, and when to contact a clinician.
1. Muscle aches and soreness
This is probably the best-known atorvastatin side effect, but it can be surprisingly subtle. You may experience:
- Aching or soreness in the thighs, calves, shoulders, arms, or back
- Muscle tenderness
- A feeling similar to having exercised too hard
- General muscle discomfort without an obvious injury
The important point is that not every muscle ache occurring while taking atorvastatin is caused by atorvastatin. In controlled trials, the difference between statin and placebo groups has generally been small.
Risk can be greater with higher statin exposure, certain interacting medications, kidney or liver problems, hypothyroidism, older age, and some other medical circumstances.
2. Muscle weakness or unusual fatigue
Some people notice weakness rather than pain. For example, you might find that climbing stairs, getting out of a chair, or lifting objects becomes unexpectedly difficult.
Weakness accompanied by significant muscle pain, fever, extreme tiredness, or dark urine deserves prompt medical attention because it can indicate significant muscle injury.
3. Rare rhabdomyolysis — severe muscle breakdown
This is extremely uncommon but potentially dangerous.
Rhabdomyolysis occurs when muscle tissue breaks down and releases substances into the bloodstream that can damage the kidneys. Warning signs include:
- Severe muscle pain
- Marked muscle weakness
- Extreme fatigue
- Fever
- Dark/brown urine
- Reduced urination
The FDA labeling warns about myopathy and rhabdomyolysis, while the American Heart Association describes serious statin-associated muscle injury as rare.
Dark urine together with severe muscle symptoms should not be ignored.
4. Liver-enzyme elevations
Atorvastatin can cause increases in liver enzymes such as ALT and AST.
Importantly, an elevated liver enzyme test does not automatically mean that the liver is being permanently damaged. Actual serious liver injury from statins is rare.
Possible symptoms of significant liver problems include:
- Unusual fatigue
- Loss of appetite
- Nausea
- Upper-right abdominal pain
- Dark urine
- Yellow skin or eyes
- Unusual bruising
These symptoms warrant prompt medical evaluation.
5. Diarrhea and digestive upset
Atorvastatin can cause gastrointestinal symptoms, including diarrhea, gas, heartburn, nausea, and stomach discomfort.
In clinical trials, diarrhea occurred among the adverse reactions reported with Lipitor.
For some people, these symptoms are mild and disappear as the body adjusts. Persistent or severe diarrhea should be discussed with a healthcare professional because it can also have completely unrelated causes.
6. Memory problems or forgetfulness
This is one of the side effects that people often find surprising.
Some people taking atorvastatin have reported:
- Forgetfulness
- Difficulty concentrating
- Feeling mentally “foggy”
- Temporary memory problems
- Confusion
The current MedlinePlus information specifically lists forgetfulness, memory loss, and confusion among possible atorvastatin adverse effects.
However, there is an important distinction: reports of cognitive symptoms do not establish that atorvastatin commonly causes cognitive impairment. The American Heart Association found no convincing evidence of a causal relationship between statins and cognitive dysfunction.
If you develop a new or persistent cognitive problem after starting atorvastatin, tell your clinician rather than simply stopping the medicine.
7. Increased blood sugar or development of diabetes
Statins, including atorvastatin, can produce a small increase in blood glucose and HbA1c in some people.
The risk is particularly relevant in people who already have diabetes risk factors such as:
- Prediabetes
- Metabolic syndrome
- Obesity
- Elevated fasting glucose
- Higher baseline HbA1c
The FDA labeling specifically warns about increases in HbA1c and fasting serum glucose.
The overall increase in diabetes risk is small, and for people who need a statin to reduce cardiovascular risk, the cardiovascular benefits generally outweigh this risk.
8. Joint pain
Joint pain (arthralgia) is another reported adverse effect that can be overlooked because it is often attributed to aging, arthritis, exercise, or another condition.
MedlinePlus lists joint pain among atorvastatin’s possible side effects.
If joint pain begins soon after starting or increasing atorvastatin and has no obvious explanation, mention the timing to your clinician.
9. Nausea
Some people experience:
- Nausea
- Upset stomach
- Reduced appetite
- Occasionally vomiting
Nausea was reported in clinical studies of atorvastatin, although it is not among the most serious adverse reactions.
Persistent nausea accompanied by abdominal pain, dark urine, jaundice, or severe fatigue deserves medical evaluation because those symptoms could indicate a liver problem rather than ordinary stomach upset.
10. Headache and nonspecific symptoms
People taking atorvastatin may experience nonspecific symptoms such as tiredness or feeling generally unwell. The FDA labeling includes tiredness among additional adverse effects reported with Lipitor.
Because fatigue and headaches have many possible causes, it is difficult to determine from symptoms alone whether atorvastatin is responsible.
The timing is useful: symptoms that consistently begin after starting or increasing the medication deserve discussion with your healthcare professional.
11. Tendon problems
Tendon problems have been reported with atorvastatin and other statins. The FDA labeling lists tendon problems among additional adverse reactions reported with Lipitor.
You might notice:
- Persistent tendon pain
- Tenderness
- Swelling
- Difficulty using the affected area
The evidence for a causal connection between statins and tendon disorders is not as strong as it is for muscle-related adverse effects. The American Heart Association notes that evidence does not establish a convincing causal relationship for tendonitis.
12. Allergic reactions
Rarely, atorvastatin can cause a hypersensitivity/allergic reaction.
Potential warning signs include:
- Hives
- Itching
- Facial swelling
- Swelling of the lips or tongue
- Throat swelling
- Difficulty breathing or swallowing
- Hoarseness
Severe breathing difficulty or swelling of the face, mouth, or throat is an emergency.
13. Immune-mediated necrotizing myopathy
This is a particularly unusual muscle complication.
Unlike ordinary statin-associated muscle symptoms, immune-mediated necrotizing myopathy (IMNM) can persist even after the statin is discontinued because the immune system becomes involved.
The FDA specifically identifies immune-mediated necrotizing myopathy as a warning associated with atorvastatin.
A key clue is persistent muscle weakness that doesn’t resolve after the medication has been stopped. This requires medical investigation.
14. Drug and food interactions that increase side-effect risk
This isn’t technically a “side effect” by itself, but it’s one of the most important lesser-known issues with atorvastatin.
Some medications can increase atorvastatin concentrations in the body, potentially increasing the risk of muscle toxicity. The risk of statin-associated myopathy is related to circulating drug concentrations and can increase when other drugs interfere with statin metabolism.
Examples of potentially important interactions include certain:
- Antibiotics
- Antifungal medicines
- HIV medications
- Other cholesterol-lowering drugs
- Immunosuppressive medicines
- Certain heart medications
Grapefruit/grapefruit juice can also interact with atorvastatin, so it’s worth asking your pharmacist or physician how much is safe for you.
Always give your clinician a complete list of prescription medicines, over-the-counter medicines, vitamins, and supplements.
15. Kidney problems secondary to severe muscle injury
Atorvastatin isn’t generally considered a common direct cause of kidney damage. The important connection is that severe muscle breakdown (rhabdomyolysis) can injure the kidneys.
This is why severe muscle symptoms plus dark urine, weakness, or reduced urination are particularly concerning.
Ordinary mild muscle aches are very different from rhabdomyolysis, which is rare.
🚨 Symptoms that should not be ignored
Contact a healthcare professional promptly if you develop:
- Unexplained severe muscle pain
- Significant muscle weakness
- Severe or rapidly worsening fatigue
- Dark/brown urine
- Yellow skin or eyes
- Upper-right abdominal pain
- Severe nausea/vomiting
- Unusual bruising or bleeding
- Persistent confusion or major cognitive changes
Seek emergency medical attention for difficulty breathing, severe swelling of the face/throat, or other signs of a severe allergic reaction.
An important point about stopping atorvastatin
Don’t stop atorvastatin on your own simply because you experience a possible side effect. Statins are used to reduce the risk of heart attack and stroke, and the American Heart Association concludes that, for people who appropriately need statin therapy, the cardiovascular benefits generally outweigh the small risks of serious adverse effects.
If you develop symptoms, your clinician may determine whether they are actually related to atorvastatin, check appropriate laboratory tests, look for other causes, adjust the dose, change the timing, or consider another statin or cholesterol-lowering treatment.
Bottom line: the most important potentially serious effects to recognize are significant muscle injury, liver injury, severe allergic reactions, and persistent immune-mediated muscle disease. Memory complaints, digestive symptoms, joint pain, and blood-sugar changes can occur or be reported, but the evidence varies considerably regarding whether atorvastatin itself causes every symptom attributed to it.
This information is educational and isn’t a substitute for individualized medical advice.