What to Know About Drug-Induced Thrombocytopenia

Scientific evidence suggests that numerous drugs are highly likely to cause drug-induced thrombocytopenia. They include:

• abciximab, a blood thinner that helps slow down the process of blood clotting
• acetaminophen (Tylenol), a pain reliever that also reduces fever
• heparin, an anticoagulant meant to help slow down blood clotting in blood vessels
• methyldopa, a blood pressure medication
• quinidine, a medication that treats irregular heartbeat and malaria
• quinine, an antiparasite medication that treats malaria
• rifampin, an antibiotic that doctors use with other medications to treat tuberculosis

Research suggests that a few other drugs might also cause drug-induced thrombocytopenia, including:

• carbamazepine, an anticonvulsant medication that treats seizures and bipolar disorder
• cimetidine, an antihistamine that people use as a stomach acid reducer to help treat stomach ulcers
• diclofenac, a nonsteroidal anti-inflammatory drug (NSAID) to treat pain from arthritis and migraine
• efalizumab, a biologic helpful in treating autoimmune conditions, like psoriasis
• trimethoprim-sulfamethoxazole, an antibiotic to treat infections
• vancomycin, an antibiotic that doctors often use to treat methicillin-resistant Staphylococcus aureus

Symptoms of drug-induced thrombocytopenia to watch out for include:

• bleeding in places you don’t normally bleed
• bleeding from small cuts or scrapes that don’t heal very quickly
• having more frequent nosebleeds than usual
• bleeding from your gums when you brush your teeth
• bruising more easily than usual
• developing red spots on your skin (petechiae)
• developing discolored spots on your skin (purpura)
• having blood in your urine
• having blood in your stool
• having blood in your semen or vaginal discharge

Seek immediate medical help if you have any of the symptoms of drug-induced thrombocytopenia for longer than a week or if you notice any emergency symptoms. These include:

• bleeding that doesn’t stop even with bandages or applying pressure
• extreme fatigue
• loss of consciousness (syncope)

Some diagnostic tools and techniques that doctors might use to diagnose drug-induced thrombocytopenia include:

• blood tests to check for low platelet levels and other irregular levels of blood cells, such as red blood cells or white blood cells
• a physical exam to check for other signs of thrombocytopenia, such as an enlarged spleen (splenomegaly) or signs of excessive bleeding
• the removal of any drugs from your treatment plan that may be causing thrombocytopenia

The first-line treatment for drug-induced thrombocytopenia is immediately stopping the drug that’s causing it.

You may also need to stop taking other medications that may have triggered thrombocytopenia by interacting with the medication that induced the condition.

Your doctor may recommend that you stop taking medications in a specific sequence so that they can monitor how your symptoms change after stopping each medication.

They may also order blood tests before and after you stop each medication to monitor how your platelet counts respond.

If you’re taking the drug to treat or control another condition with chronic or severe symptoms, such as high blood pressure or diabetes, your doctor will likely prescribe or recommend another medication that can control your symptoms instead.

In most cases, drug-induced thrombocytopenia resolves within 2–5 days after stopping the medication that’s triggering it.

In more complex or severe cases, it might take weeks for platelet counts to return to typical levels.

This condition can be life threatening without prompt treatment. It can also be severe if a complex set of interactions between multiple medications induces the condition.

Here are some of the most frequently asked questions about drug-induced thrombocytopenia.

What’s the most common cause of drug-induced thrombocytopenia?

Heparin is the most common cause of drug-induced thrombocytopenia.

What chemicals can cause thrombocytopenia?

Other chemicals known to cause thrombocytopenia include chemotherapy medications, alpha interferon (a liver condition treatment), and ethanol.

What medications cause high platelets?

NSAIDs are a common medication known to cause high platelets. Corticosteroids for relieving joint pain, often in the form of injections, may also increase your platelet count.

Other medications that may cause a high platelet count include the hormone epinephrine and the antibiotics azactam and ceftazidime.

Numerous medications, especially heparin, can cause thrombocytopenia. This is a dangerously low platelet count.

Seek immediate medical help if you have any symptoms of low platelet count, especially if you’re taking one or more of the medications known to cause drug-included thrombocytopenia.