Antibiotics & Antiparasitics
How to Take Stromectol (Ivermectin) Safely
About Stromectol
Stromectol (ivermectin) is an antiparasitic medication used to treat strongyloidiasis (threadworm infection) and onchocerciasis (river blindness), and it is also prescribed off-label for conditions such as scabies and head lice when topical treatments fail or are impractical.
Ivermectin is dosed by body weight, and for many infections a single dose — sometimes repeated weeks or months later — is the entire treatment. That makes taking the dose correctly especially important.
The most important rule is simple but frequently missed: ivermectin tablets are taken on an empty stomach with water. This guide explains why, plus what to expect after dosing and how follow-up testing confirms the infection is gone.
How to Take Stromectol: Step by Step
Take ivermectin exactly as prescribed. Your dose is calculated from your body weight — often several 3 mg tablets at once — so confirm the tablet count with your pharmacist if anything is unclear.
Take the dose on an empty stomach: at least 1 hour before or 2 hours after a meal.
Swallow the tablets with a full glass of water (8 oz / 240 mL).
For strongyloidiasis, a single dose is typical, though your prescriber may repeat it. For onchocerciasis, doses are commonly repeated every 3–12 months. Follow the exact schedule you were given.
Complete all follow-up testing. Strongyloidiasis requires follow-up stool examinations to prove the parasite has been eradicated — feeling better is not proof of cure.
If you feel dizzy or lightheaded after dosing, rise slowly from sitting or lying positions, and avoid driving until you know how the medication affects you.
What to Avoid While Taking Stromectol
- Food — taking ivermectin with a meal substantially increases absorption and side-effect risk. Keep the empty-stomach rule unless your prescriber specifically tells you otherwise.
- Alcohol — avoid around dosing days; it can worsen dizziness and drowsiness and adds liver strain.
- Loiasis (Loa loa) risk — tell your prescriber if you have ever lived in or visited West or Central Africa. Treating someone with a heavy Loa loa co-infection can trigger serious, rarely fatal, brain reactions, and a screening blood test may be needed first.
- Mazzotti reactions during onchocerciasis treatment — itching, rash, fever, swollen lymph nodes, joint pain, or eye changes in the first days after dosing reflect the parasite die-off. Report them, especially any eye symptoms.
- Sedating medications — ivermectin can add to the drowsiness of sleep aids, anti-anxiety drugs, and opioids. Give your pharmacist a full medication list.
- Pregnancy and breastfeeding — safety is not established. Tell your prescriber if you are pregnant, might be, or are nursing before taking a dose.
Frequently Asked Questions
Why must ivermectin be taken on an empty stomach?
Food — especially fatty food — can roughly double the amount of ivermectin absorbed. For parasitic infections, prescribers want blood levels that are effective but predictable, because higher exposure raises the risk of side effects without improving parasite killing. Water and an empty stomach keep that balance.
How soon does ivermectin work?
It begins paralyzing and killing susceptible parasites within days of the dose. Note that with scabies, itching commonly persists for 2–4 weeks after successful treatment — this is a lingering allergic reaction to the dead mites, not proof the treatment failed.
Will I need more than one dose?
It depends on the infection. Strongyloidiasis is often treated with a single dose (sometimes repeated); onchocerciasis is typically re-dosed every 3–12 months because the drug kills larvae but not adult worms; scabies is commonly two doses, 7–14 days apart. Follow your prescriber's plan exactly.
What side effects should I expect?
The most common are dizziness, nausea, diarrhea, abdominal pain, fatigue, and itching or rash — usually mild and gone within a few days. Fever, swollen glands, or eye irritation during onchocerciasis treatment, or any severe or persistent symptom, should be reported to your prescriber.
Can I take ivermectin with my other medications?
Often yes, but interactions exist. Warfarin users may see INR changes and need monitoring, and drugs that affect CYP3A4 or P-glycoprotein (some antifungals, antibiotics, and seizure medicines) can alter ivermectin levels. Always review your complete medication list with the dispensing pharmacist.
Is ivermectin safe for children?
For its approved indications, ivermectin tablets are used in children weighing at least 15 kg (about 33 lb), with weight-based dosing set by the prescriber. It is not established for children below that weight.