Infestations: Signs, Causes, and Safe Treatment Options

Some pests and parasites are obvious. Others hide for weeks. Whether it's itchy bites, stomach pain, or unexpected hair loss, knowing what to look for and what to do first saves time and stress. This guide keeps things practical: how to spot common infestations, quick home steps you can take, and when prescription meds are needed.

How to spot common infestations

Head lice: intense itching at the scalp, small white nits stuck to hair shafts, and small red sores from scratching. Lice are most common in kids but spread fast in households.

Scabies: a relentless, worsening itch that’s often worse at night and between fingers, wrists, or around the waist. You may see thin, threadlike burrows or a rash in these areas.

Intestinal worms: symptoms can be vague—stomach pain, diarrhea, unexplained weight loss, or visible worms in stool. Some infections cause no symptoms at first, so testing can be the only way to know.

Fleas and bedbugs: bites in lines or clusters on arms and legs, tiny dark droppings on bedding for bedbugs, or seeing the pests on pets for fleas. Pets often carry fleas into the home.

Treatment options: home care to prescription meds

Start practical: wash bedding and towels in hot water (60°C/140°F) and dry on high heat. For items that can’t be washed, seal them in plastic for 48–72 hours. Vacuum floors and furniture and treat pets for fleas with vet-recommended products.

Over-the-counter options work well for many cases. For lice, medicated shampoos with permethrin plus wet-combing with a fine-tooth comb usually clears infestations when done carefully and repeated as directed.

Scabies often needs a prescription topical like permethrin cream applied to the whole body, and sometimes an oral option—ivermectin—is used for large outbreaks or when creams fail. Ivermectin is also used for certain worm infections; talk to your provider about the right choice and dosing.

Intestinal parasites need targeted meds: albendazole, mebendazole, praziquantel, or ivermectin depending on the worm. Don’t guess—get a stool test or a doctor’s diagnosis so you take the right drug.

Important safety note: avoid random online purchases of prescription meds without a valid prescription or a trusted pharmacy. If you research buying meds online, pick reputable pharmacies and check reviews, licensing, and return policies. Our site has articles that explain safe online pharmacy practices and review alternatives for certain drugs.

When to see a doctor: severe symptoms, signs of spreading infection, persistent symptoms after treatment, young children, pregnant or breastfeeding people, or if you have a weakened immune system. A clinician can confirm the cause, prescribe the correct drug, and advise household treatment to prevent reinfestation.

Quick checklist: 1) Identify symptoms, 2) Isolate affected items, 3) Start recommended cleaning, 4) Use appropriate OTC or prescription treatment, 5) Treat close contacts and pets if needed, 6) Follow up with a provider if symptoms persist.

Got questions about a specific pest or a medicine you were told to try? Check our detailed guides on treatment options and safe medication sources, or reach out to a healthcare provider for personalized advice.