Levamisole safety: risks, warning signs, and what to do

Levamisole is an anti-parasitic drug mostly used in animals today. It also shows up as a contaminant in illegal drugs like cocaine. That mix-up is a big reason people worry about levamisole safety: even small exposures can cause serious problems. This page gives clear, practical steps to spot trouble and act fast.

Common risks and how they show up

The two main issues to watch for are blood cell damage and immune-related injuries. Levamisole can cause agranulocytosis or severe neutropenia — that means your white blood cell count can drop a lot, leaving you open to infections. Warning signs include fever, sore throat, mouth sores, and unusual tiredness.

Another problem is vasculitis, where small blood vessels get inflamed. That can cause purplish skin lesions, open sores, or patches of skin that turn black. These skin findings are especially linked to levamisole when it’s mixed into street drugs. Some people also develop autoantibodies that doctors may test for if vasculitis is suspected.

Side effects can start days to weeks after exposure. Even if you feel fine right after using a product that might contain levamisole, problems can still show up later. That delayed timing is why checking early matters.

What to do if you think you were exposed

If you have a fever, sore throat, unexplained bruises, severe fatigue, persistent skin sores, or signs of infection — get medical care right away. Tell the clinician you may have been exposed to levamisole or that you used a substance that could be contaminated. That helps them pick the right tests.

Key tests doctors may order are a complete blood count (CBC) with differential to check white cells, and tests for inflammation or autoimmune markers if vasculitis is suspected. If white blood cell counts are very low, doctors may admit you for monitoring and give antibiotics or other treatments as needed.

Avoid further exposure. If the levamisole came from a drug supply, stop using that source and consider drug-checking services if available in your area. If you’re taking any prescribed meds, tell your provider so they can check for interactions.

Pregnant people and those with weak immune systems should be extra careful. Levamisole-related blood problems and infections are more dangerous in these groups. Always mention pregnancy or immune conditions when you seek care.

Bottom line: levamisole can be dangerous even in small amounts. Safe use means avoiding unknown or illicit products, watching for fever, sore throat, and skin changes, and getting prompt medical attention with CBC testing if you suspect exposure. Quick action can prevent serious complications.