Kilograms decide how many 3 mg tablets you stack

Kilograms decide the stack, not a shared bottle

Prescribers multiply micrograms by kilograms, then round to chips.

Stromectol is a 3 mg human tablet. The prescription is not 'take one like an aspirin.' Someone multiplies a mcg/kg rate by your actual weight, then stacks whole chips to land near that milligram total. A 55 kg adult and a 90 kg adult should not swallow the same count. Rounding to the nearest available tablet is normal. Kitchen-scale heroics are not.

That is why this desk talks about a chart before anyone talks about ordering. If the weight on the slip is a guess, the stack is a guess. If two people in a household share leftover chips 'because scabies is scabies,' one is under and one is over. Same calendar. Different piles.

The parent product notes are on the ivermectin page. Who even earns a chip is a different article: which parasites make the list. This file stays on arithmetic, stomach clock, and the reactions people misread as poisoning.

Two label rates live on the same blister

Strongyloidiasis usually aims near 200 mcg per kilogram.

US labeling for intestinal Strongyloides is about 200 mcg/kg as a single oral day, sometimes repeated, then a clearance check. Onchocerciasis is about 150 mcg/kg, and the calendar is longer because adults survive. Scabies, when we use the oral chip, usually follows the 200 mcg/kg neighborhood on two days spaced a week or two apart so hatched mites meet a second pass.

Those are not internet 'protocols' you remix. The gap between doses tracks the parasite's life cycle. Skip the second scabies day and you meet the next generation. Treat river blindness like a one-shot Strongyloides clear and the larvae return. The table below is a shape, not your personal slip.

Children need a measured weight, not a borrowed adult stack. The smallest infants are generally outside this tablet's usual use. Pregnancy is a clinician call, not a home chart. If Loa loa geography is in the history, screening can change whether we dose at all.

Water on an empty stomach is the classic clock

Stromectol's older label still says empty stomach plus water.

Swallow the chips whole with a full glass of water. The classic US direction is an empty stomach. Food, especially fat, raises absorption, which means a home decision to take the stack with a heavy meal quietly lifts the level above what the prescriber counted. Neither clock is 'wrong' in the abstract. Switching clocks on your own is.

There is no prize for splitting the day's chips across breakfast and dinner. Take the counted pile as directed. If a second scabies day is on the plan, mark it the morning you take the first. People forget once the worst itch eases.

Miss a scheduled day? Ask how to restart. Do not double the next pile. Past the intended milligram total you collect dizziness and nausea, not a stronger cure. Alcohol the same night is a poor mix because both can make you light-headed.

Mazzotti is dying larvae, not a poison stamp

Itch and fever after a filarial dose often mean debris.

At a labeled human stack, a lot of people feel nothing. When something shows up it is usually brief: headache, a wave of dizziness, mild nausea. Separate from that is the Mazzotti picture after a heavy microfilarial load, especially in onchocerciasis. Larvae die in a crowd. The body reacts with itch, rash, tender nodes, aches, sometimes a short fever. That is dying-microfilariae immunology, not proof 'the drug is poison.'

A routine scabies course in a household with a modest mite load rarely looks like a textbook Mazzotti day. Do not brace for a storm you are unlikely to get. Do watch for a different picture: confusion, severe drowsiness, marked unsteadiness, vision change, a sudden blood-pressure drop, or a seizure. Those are overdose or neurologic red flags, and they cluster with livestock paste and guessed ribbons, not with a counted 3 mg pile.

Loa loa is the geographic exception that can turn a die-off dangerous. Say if you lived in that belt. Keep any leftover paste out of a child's reach. A horse tube on a bathroom shelf is a poisoning waiting for a curious hand.

Livestock paste is not a cheaper 3 mg chip

Horse syringes are built for animals of several hundred kilograms.

Farm paste and cattle pour-ons are concentrated for livestock. Inactive ingredients were chosen for animals. There is no honest way to squeeze a human 3 mg increment from a horse syringe by eye. Poison-center spikes during the COVID years were this product error in public. People vomited, grew confused, and some seized.

If a household needs ivermectin, the product is a human tablet counted to kilograms. Savings at a feed store are not a discount. They are a concentration mismatch. The COVID claim that sent people to those aisles is unpacked in the trial file.

Tell the prescriber the other drugs you take, including sedating ones. Ivermectin is not a clash-heavy molecule, but it can add drowsiness, and liver disease deserves a slower look. None of that replaces the first rule: human chips, human weight, human indication.

Rechecks matter more than a quiet week

Feeling well after Strongyloides treatment is not proof of clearance.

Strongyloides can persist quietly. We recheck weeks later because a survivor plus later steroids is how hyperinfection starts. A positive follow-up means another counted course, not a verdict that the molecule 'failed.' For scabies, success is the end of new burrows, not the end of itch. Judging cure by itch alone makes people redose for healing skin.

Onchocerciasis follow-up lives inside a program, not a single home test. In every case the recheck exists because catching persistence early is cheaper than a late crash. If you are about to start high-dose steroids or chemotherapy, that recheck is not optional on this desk.

Bring a current weight to the visit. Wear the same honesty about travel. Then let someone who can see the blister count the chips. Do not invent a third mcg/kg rate because a video said 'more is safer.'

Stack the chips, then stop guessing

Bring the kilogram number to the visit, not a farm tube.

Count from weight. Use the rate that matches the bug - about 200 mcg/kg for Strongyloides and most oral scabies plans, about 150 mcg/kg for onchocerciasis. Swallow with water on the stomach clock you were given. Read leftover itch and short aches as possible debris, not as proof the molecule is poison. Treat confusion or a seizure as an emergency.

Who earns the chip is in the parasite map. Why a virus never did is in the COVID file. Label-level notes sit on ivermectin. Dr. Ivy Chukwu takes the chart questions below.

Do not change a stack without the clinician who knows your weight and your other medicines. The legal floor is the desk disclaimer.

Consultation

Reader questions, answered

Answered by Dr. Ivy Chukwu, MD · Infectious disease & internal medicine

Kilogram-stack questions that land after the chart.

Hector Ruiz asksMy partner and I both have scabies. Why is her chip count different from mine?

Because the count is kilograms times a mcg/kg rate, then rounded to 3 mg tablets. Unless you weigh the same, the piles should differ. The calendar should match - usually two days about a week or two apart, household treated together - so mites cannot commute. People get stuck because most bottles in a cabinet are 'one tablet for any adult.' Stromectol is not that bottle. If you copy her four chips and you weigh twenty kilograms more, you underdose. If she copies your six, she overshoots. Same days. Different stacks. CDC scabies treatment pages at the CDC keep the household rhythm in one place if the paper slip goes missing.

Maeve O'Brien asksThe slip says empty stomach. A neighbor says food makes it 'work better.' Who is right?

Your slip is right for the dose you were given. The classic Stromectol label is water on an empty stomach. A fatty meal does raise absorption, which is exactly why a neighbor's 'take it with dinner' tip is not a free upgrade. It changes the level the prescriber already counted. If a clinician wanted the fed state, they would say so and set the stack for that clock. Do not freelance. Swallow the chips whole with a full glass of water. Mark the second scabies day the morning you take the first. MedlinePlus dosing notes at MedlinePlus match the empty-stomach tradition if you need a public-language reminder next to the pharmacy label.

Yusuf Rahman asksI ached and itched the day after a filarial dose. Is that the chip attacking me?

More often it is larvae dying in a crowd. We call that a Mazzotti reaction: itch, rash, tender nodes, muscle aches, sometimes a short fever. It is immunology to debris, not a stamp that 'the drug is poison.' It usually settles in a day or two with rest and a simple antihistamine. A routine mite course with a light load rarely looks like that textbook day, so do not borrow someone else's filarial story. The picture that should move you toward urgent care is different - confusion, hard-to-wake drowsiness, marked unsteadiness, vision change, a sudden blood-pressure drop, or a seizure - especially after a livestock product. Ordinary aches after a counted human stack are not that picture.

Claire Dufresne asksThe feed store paste is cheaper. Can I measure a human ribbon from the syringe?

No. That syringe was built for an animal of several hundred kilograms. The paste is more concentrated than any 3 mg human chip, and the fillers were chosen for livestock. A ribbon that looks small can be many times a human total. People who guess have vomited, grown confused, and seized. There is no kitchen conversion that makes a horse tube into Stromectol. If a human needs ivermectin, the product is a counted pharmacy tablet. The money you think you save is the concentration mismatch. If COVID headlines sent you to that aisle, read the myths file. FDA consumer pages at the FDA said the same thing in plainer words.

Benito Alvarez asksWe are expecting and there was a parasite exposure. Can she take the chips?

That is a visit, not a chart you run at home. We often defer ivermectin in pregnancy unless the infection is serious enough that treating clearly beats the thinner safety file. Sometimes waiting until after delivery is the safer path. Sometimes the worm is the bigger threat. Gestational age, which parasite, and how heavy the load all change the call. Do not self-start a 3 mg stack because a relative mailed leftover tablets. Bring the exposure story and any test results. We will read the current label and obstetric guidance with you, not from a forum dose table. NIH's public library at NCBI is a place to sit with primary sources if you like to read ahead of the appointment.

Ingrid Solberg asksI feel fine after Strongyloides treatment. Why a stool check weeks later?

Because this worm can persist without making you feel ill, and a quiet survivor plus later steroids is how hyperinfection starts. A follow-up test is how we learn whether the counted course finished the job. A positive result means another weight-based round, not a scandal about the molecule. Feeling well is nice. It is not clearance. For scabies we watch for new burrows instead of running that same stool test, because leftover itch is healing skin. If you are heading into chemotherapy or a long steroid taper, I treat the recheck as mandatory. Catching a leftover larva now is a clinic visit. Catching it during hyperinfection is an ICU.

Anika Bose asksI forgot the second scabies day. Do I double tomorrow?

Do not double. Call the prescriber and ask how to place the late day. The second pass exists because eggs hatch after the first, not because the first 'failed' and needs a hammer. Two piles on one morning just raise the chance of headache and dizziness. Keep treating household contacts on a shared calendar and keep doing the laundry, or a perfect personal stack still loses to a roommate's untreated mattress. If new burrows are already marching, that is extra reason to speak with the clinic rather than invent a third day. The ivermectin monograph and this chart are teaching notes, not a rescue protocol you run at 11 p.m.

Wesley Grant asksWe still have horse paste in the barn bathroom. Is that a kid risk?

Yes. A livestock tube is a concentrated product, and a child who treats it like toothpaste can take a neurologic overdose. Confusion, vomiting, unsteadiness, and seizures are the pattern we do not want to meet after a Saturday in the barn. Store it the way you would store any poison, or better, do not keep a human-tempting tube in a house that does not have a large animal under a vet's plan. Human leftover 3 mg chips also belong in a closed bottle, not a saucer. If a child swallows paste, call poison control or emergency services and bring the tube so they can read the concentration. Do not wait to see if it 'wears off.'

General education from a clinician, not personal medical advice. Bring your own history to your own prescriber.