Why do you write day 1 and day 8 instead of one big swallow?
Day 1 and day 8 is the scabies card
Two dates. One mite. The second swallow is the point of the card.
Mites keep hatching after a single swallow. Sarcoptes scabiei eggs sit in burrows and are not reliably killed by one oral pass. CDC clinical-care language for classic scabies, when a clinician chooses oral ivermectin, is two doses at 200 mcg/kg, spaced 7 to 14 days. This desk writes day 1 and day 8 so the second date is a calendar, not a vibe. Skip the second date and you treat the parents and leave the nursery.
The US Stromectol label does not list scabies. Intestinal Strongyloides stercoralis and Onchocerca volvulus own that row. Oral ivermectin for mites is a clinic judgment after permethrin 5% cream, a failed topical, a household that cannot complete a neck-to-toe rub, or a setting where oral coverage of contacts is the cleaner public-health move. Off-label is not a license to invent a 12 mg tablet. It is a license to count 3 mg chips twice.
Itch can linger two to four weeks after the mites are dead. That is post-scabetic inflammation, not automatic failure. New burrows after day 8, or a household that never treated the sofa and the sheets, is a different thread. Malik marks the dates first. Then he talks about cream, laundry, and who else in the apartment needs a card.
The US oral tablet is still only 3 mg
Count chips. Do not invent a bigger human tablet for mites.
American pharmacies stock one oral tablet strength. Stromectol and the generic twins are 3 mg. There is no licensed 6 mg or 12 mg human chip on this shelf. A 12 mg fasting study dose in the label is four of those 3 mg tablets, not a different product. People who ask for 'the 12 mg scabies pill' are mixing a calculated swallow with a strength that does not exist.
The 3 mg chip is an 80:20-class mix of two closely related avermectins, with H2B1a as the major measured component. After single 12 mg fasting doses in healthy volunteers (a mean of about 165 mcg/kg), mean peak H2B1a levels sat near 46.6 and 30.6 ng/mL at about four hours in two studies. Those numbers belong to a human tablet taken as studied. They do not belong to a livestock tube with a different concentration and a different excipient list.
Veterinary paste is the wrong product even when the INN matches. Concentration marks on a horse syringe assume a half-ton animal. Some pastes carry solvents that were never cleared for a human gut. Poison-control spikes during the COVID years were a category error: animal product, human swallow, no weight band, no day-8 card. Cheap Stromectol 3 mg is a pharmacy count. A tack-room tube is not a bargain version of the same point.
How 200 mcg/kg becomes a 3 mg chip count
| Mark on the card | Target | 3 mg habit |
|---|---|---|
| Classic scabies (off-label) | ~200 mcg/kg day 1 and day 8 | Weight band; whole tablets |
| Household contact (clinic call) | Same math if treated | Same dates; laundry the same day |
| Intestinal Strongyloides (labeled) | ~200 mcg/kg once | Stool check after; not a mite card |
| Weight under 15 kg / pregnancy | Not established | Do not improvise a chip |
Weigh the person the morning you write the card. Jeans memory from last winter is how a 90 kg adult leaves with a 70 kg count. Intestinal strongyloidiasis on the label already uses about 200 mcg/kg as a single oral target, and the 3 mg tablet forces weight bands that slightly overshoot rather than undershoot. Scabies clinics borrow that same math and then repeat it on day 8. You do not split a chip. You read the band and swallow whole tablets.
The labeled Strongyloides bands are the practical scabies counter as well: 15-24 kg takes 1 tablet, 25-35 kg takes 2, 36-50 kg takes 3, 51-65 kg takes 4, 66-79 kg takes 5, and 80 kg or more is calculated at 200 mcg/kg. A 70 kg adult is five chips (15 mg, a little over 14 mg). An 80 kg adult is about 16 mg, which is six chips. Two dates for that adult is ten to twelve tablets. That is why a 3 mg x 20 pack shows up on this cheap-fill map - two household adults, or one adult plus a planned leftover that should not wander into a neighbor's virus story.
Weight under 15 kg is a stop. Safety and effectiveness were not established there. Pregnancy is a stop. Animal work showed cleft palate and, in rabbits, clubbed forepaws at or near maternotoxic doses; there are no adequate human pregnancy trials. The label says do not use because safety is not established. A mite in a pregnant person or a small child is a specialist conversation about topical options, not a kitchen count of leftover chips.
A meal for mites, an empty gut for labeled worms
Absorption
Oral. Labeled worms: fasting with water. Scabies clinics often give the 200 mcg/kg pass with food. Peak of the major component near 4 hours. A high-fat meal raised bioavailability about 2.5-fold in a 30 mg study.
Distribution
Wide tissue reach, where mites and worms actually live. P-glycoprotein limits CNS entry at ordinary human exposure.
Metabolism
Hepatic, mainly CYP3A4, to several metabolites. Strong CYP3A4 inhibitors can lift systemic levels.
Excretion
Almost entirely fecal over about 12 days; urine under 1%. Parent half-life about 18 hours.
Labeled worms want water and an empty stomach. That is the Stromectol pharmacokinetics line. A 30 mg dose after a standard high-fat meal (48.6 g of fat) raised bioavailability about 2.5-fold versus the same 30 mg fasted. Approved weight bands for Strongyloides and oncho were studied fasting. A bacon plate quietly turns a labeled worm count into an unstudied exposure.
Scabies experts flip that advice on purpose. CDC clinical-care notes say that although ivermectin guidelines recommend an empty stomach, mite clinicians often give the 200 mcg/kg swallow with food to push bioavailability into skin and burrows. That is a specialist habit, not a license to 'eat extra so you can skip a chip.' Malik writes the meal rule next to the dates when the mark is a mite, and he writes fasting water when the mark is a named nematode. Mixing the two rules is how a resident double-doses a worm or under-doses a mite.
Peak plasma sits near four hours. The parent half-life is about 18 hours. Almost all of the dose leaves in feces over roughly twelve days; less than 1% shows up in urine. CYP3A4 does the main hepatic work; CYP2D6 and CYP2E1 show up in vitro at a much smaller share. P-glycoprotein helps keep ordinary levels out of the brain. A fatty meal plus a strong CYP3A4 inhibitor is how you start arguing with that margin - especially if someone then invents a third date because 'the itch is still there.'
Permethrin still sits on the labeled scabies shelf
First-line cream still sits on the FDA scabies shelf. Permethrin 5% from the neck down, left on the labeled hours, repeated in a week, is the ordinary US start for classic scabies. Oral ivermectin enters when cream fails, when the person cannot complete a full-body rub, when nails and scalp need a systemic assist, or when a crowded household needs a swallow that does not depend on perfect technique. The two-dose card is an add, not a trophy.
Laundry is part of the dose. Sheets, pillowcases, and clothes worn the last three days go in a hot wash the same morning as day 1. Items that cannot be washed sit in a sealed bag for several days. Treating one person and leaving the sofa and the partner is how 'resistant scabies' gets invented in a Portland apartment. Contacts who share a bed or a towel often need their own weight-banded card on the same dates, even if they are not yet scratching.
A soil-to-Mectizan note explains why this molecule became a public-health swallow. That history does not move a mite card into a labeled row. It explains why a cheap 3 mg chip exists in the first place. Malik still wants the cream conversation before anyone prices a 20-count bottle.
Crusted skin is not a two-chip job
Crusted plaques hide mite cities, not a household itch. Norwegian or crusted scabies in a steroid-heavy, transplant, HIV, or frail host can shed thousands of mites. CDC language for that picture is oral ivermectin plus a topical, with three, five, or seven 200 mcg/kg dates depending on severity - days 1, 2, and 8 as a short set, or out to days 15, 22, and 29 when the crust is thick. A two-date card written for classic scabies will fail that host and seed the ward.
Isolation, nail trimming, and daily topical work belong on that thread. Lindane is the wrong rescue on denuded skin. Malik does not 'just add a third chip' from a leftover 20-count. He stops the blotter and calls someone who treats crusted scabies for a living. The cheap-fill table on this page is a classic-card map. It is not a crusted-scabies shopping list.
Immunocompromised Strongyloides is a different nightmare on the same molecule. Extra-intestinal larvae, gram-negative sepsis, and a host who cannot clear autoinfection are specialist work. Monthly suppression shows up in that literature. It does not belong on a mite card, and it does not belong in a kitchen.
Strongyloides and oncho still own the FDA row
1970s
Omura isolates Streptomyces avermitilis from Japanese soil and ships cultures to Merck.
1981
Ivermectin launches for animals and becomes a veterinary blockbuster.
1987
Merck pledges free Mectizan for river-blindness control for as long as needed.
2015
Omura and Campbell share the Nobel Prize in Physiology or Medicine.
Scabies card
Off-label 200 mcg/kg on day 1 and day 8 from 3 mg chips - not a labeled row.
Strongyloides and Onchocerca still own the official row. Intestinal (nondisseminated) strongyloidiasis is a single oral dose meant to deliver about 200 mcg/kg, fasting, with follow-up stools to prove eradication. The label says additional doses are generally unnecessary, then immediately asks for stool checks. Many clinicians still repeat near two weeks when autoinfection or a fragile host is in play. That repeat is judgment, not a second invented strength. Open and comparative series reported 64-100% cure after one 200 mcg/kg dose. A single 170-200 mcg/kg swallow beat albendazole (200 mg twice daily for 3 days) on cure defined as no larvae on at least two stools 3 to 4 weeks later, and matched thiabendazole 25 mg/kg twice daily for 3 days with an easier sit-through.
Onchocerciasis is about 150 mcg/kg once, fasting, with a retreatment clock of 3 to 12 months because adult worms persist in nodules. Mass programs most often use 12 months. A double-blind placebo study in the labeled set cut geometric-mean skin microfilariae 83.2% at day 3 and 99.5% at 3 months, with a greater than 90% reduction held out to 12 months. You are suppressing microfilariae, not sterilizing the nodule. Saying 'cured' after one 150 mcg/kg swallow is the wrong point.
COVID never put this milligram on a virus row. Dish work needed concentrations no labeled human swallow reaches. Large randomized trials did not move hospitalization, recovery, or death in a way that earns an indication. FDA and MedlinePlus say so in public English. A Nobel sticker from Omura and Campbell in 2015 explains a soil sample and a river-blindness program. It does not license a self-dose for a cough. The evidence blotter keeps parasite trials and the empty virus row on separate pages.
A 3 mg x 20 scabies card at four licensed counters
| Counter | Count we marked | Cash band (not a quote) | Open this chain only |
|---|---|---|---|
| Costco | 3 mg x 20 | Warehouse cash; membership may apply | Costco pharmacy |
| Walgreens | 3 mg x 20 | National chain cash; ask the window | Walgreens pharmacy |
| Target | 3 mg x 20 | CVS-run Target counter cash | Target pharmacy |
| Kroger | 3 mg x 20 | National grocery cash | Kroger pharmacy |
A twenty-count bottle is a two-date household card. Two mid-weight adults at 200 mcg/kg on day 1 and day 8 will chew through most of a 3 mg x 20 pack. This desk does not sell them. The table names four licensed counters - Costco, Walgreens, Target's CVS-run pharmacy, and Kroger - and each link opens that chain's own pharmacy page. No Rite Aid row. No coupon site dressed up as a store.
We could not pin a live, chain-specific cash figure for exactly 3 mg x 20 at every window without guessing. Guessing a dollar is how sibling desks get in trouble. So the cells stay qualitative. A nearby public snapshot: GoodRx, checked for this note, listed a 3 mg x 20 carton around $70 retail and around $32 with a coupon. That snapshot is caption text. It is not a link in a grocery row.
Costco may want a membership at the warehouse counter. Target's pharmacy is a CVS desk inside the store. Walgreens and Kroger are ordinary cash windows. Ask your own clinician which count they actually wrote. Then ask that chain. Coupon apps stay in the caption.
Loa, azoles, INR, and leftover chips
| Hold on the blotter | What lifts | Desk move |
|---|---|---|
| High-fat meal (labeled worms) | About 2.5-fold bioavailability at 30 mg | Fast with water for nematodes |
| Food with scabies swallow | Higher skin exposure, clinic habit | Write the meal next to day 1 and day 8 |
| Strong CYP3A4 inhibitors | Higher ivermectin exposure | Keep the labeled band; do not add chips |
| Warfarin | Possible INR drift | Recheck INR a few days later |
Cameroon or Congo in the history can freeze the card. People with heavy Loa loa loads in West or Central Africa can develop encephalopathy after a microfilaricide - pain, red eye, incontinence, inability to stand, seizures, coma. The label asks for pretreatment assessment and close follow-up when exposure is real. A Portland travel line that says 'Cameroon, two years' is enough to stop a mite-card chip count and call tropical medicine before any oncho-style swallow. CDC loiasis pages are the public screen; they are not a home smear kit.
A single labeled or off-label swallow is not a PDE5 minefield, but the med list still gets a minute. Chronic azoles and some macrolides slow CYP3A4. Grapefruit in bulk is the folk version of the same idea. We do not rewrite the weight band because an azole is on board. We keep the meal-or-fast rule that matches the mark, and we do not stack a homemade extra chip. P-glycoprotein inhibitors are a theoretical CNS push. Warfarin has scattered INR stories; checking INR a few days after the swallow is cheap insurance.
Neurotoxicity - somnolence, stupor, coma, confusion, death - has been reported without onchocerciasis and without Loa. Overdose, usually a veterinary product, is the familiar path. Doubling chips because 'mites are stubborn' is how you argue with the brain barrier. Leftover 3 mg tablets belong to a named person, a written kilogram, and two dates. They do not belong in a cousin's COVID story or a roommate's 'prevention' jar. If tadalafil is also on the nightstand, that is a different blotter with a nitrate hold. Do not mix the two cards.
Malik's point: two dates, one 3 mg strength
Mark the mite and the kilogram. Write day 1 and day 8. Dose about 200 mcg/kg from Stromectol 3 mg chips - the only US oral strength - and do not invent a bigger tablet. Thread cream, laundry, contacts, post-scabetic itch, crusted-skin escalation, the labeled Strongyloides and oncho rows, Loa if West or Central Africa is in the history, and the cheap 3 mg x 20 map. Point: this is an off-label two-dose card with a forty-year field molecule behind it, not a virus pill and not a farm syringe.
Bring the rash photo, the weight, and the travel list to your own clinician before anyone changes a swallow. DailyMed and CDC scabies clinical care are the public anchors. This blotter is teaching. It is not your chart.
Mail arrives with a rash photo, a weight, or a paste snapshot. I mark the mite and the two dates first. Then I talk about the 3 mg chip. These answers are teaching, not your prescription.
Because eggs hatch after the first pass. Classic scabies that uses oral ivermectin is off-label in the US, and CDC clinical-care language is two doses at 200 mcg/kg, 7 to 14 days apart. I write day 1 and day 8 so the second date is a calendar. One 200 mcg/kg swallow treats the adults that are feeding now. The nursery is still in the burrow. A 'bigger first night' does not replace the second date, and it does not create a 12 mg tablet. Count 3 mg chips twice. Wash the sheets the same morning as day 1.
The farm store paste has ivermectin on the tube. Why can I not mark the syringe for scabies?
Same INN, wrong product. Paste strength is built for livestock. The marks assume a body you do not have. Some tubes carry solvents that were never meant for a human stomach. Overdose looks like tremor, confusion, ataxia, seizures, then a depressed consciousness that belongs in an emergency bay. Human Stromectol is a 3 mg tablet counted from a weight band on two dates. A paste photo in my mail is a hold, not a dosing aid. Throw the tube back in the tack room and ask a clinician for a real card.
Do I take the 3 mg chips with breakfast or on an empty gut?
It depends on the mark. Labeled Strongyloides and oncho were studied fasting with water. A high-fat meal raised bioavailability about 2.5-fold in a 30 mg study, which is how a worm count becomes an unstudied level. Scabies experts often flip that and give the 200 mcg/kg pass with food so more drug reaches skin and burrows - CDC notes that habit explicitly. I write the meal rule next to day 1 and day 8 when the mark is a mite. I do not let anyone 'eat extra and skip a chip.' Under-dosing a named mite is a different error from over-absorbing a labeled worm.
Permethrin already failed once. Is the two-dose card automatic?
It is a conversation, not a trophy. Cream fails for technique as often as for resistance - missed scalp, missed nails, a partner who never treated, sheets that stayed on the bed. I want those holes closed before I price a 3 mg x 20 pack. When oral coverage is the cleaner move, I still keep permethrin in the plan for many adults and I still write day 1 and day 8 at 200 mcg/kg from 3 mg chips. Crusted plaques are a different job: more dates, a topical every day, isolation. A leftover classic card will not clear that host.
I lived in Cameroon for a year. Does that change a mite card?
It can freeze it. Loa loa, the African eye worm, is the hold that turns a microfilaricide into encephalopathy in people with very high blood loads. Pain, red eye, incontinence, inability to stand, seizures, coma - that list is why I stop the chip count and ask for a smear and an infectious-disease partner before any oncho-style swallow. A classic scabies card is still two 200 mcg/kg dates from 3 mg chips, but I will not write it until the travel line is honest. CDC loiasis pages explain the geography. A Portland clinic that skips the travel line is not being efficient. It is being lucky.
We are trying to get pregnant. Is a cheap 3 mg card still on the table?
I pause. Animal studies showed cleft palate and, in rabbits, clubbed forepaws at or near doses that already hurt the mother. There are no adequate, well-controlled pregnancy trials. The label says do not use because safety is not established. Weight under 15 kg is the other hard stop. If a mite in pregnancy or in a small child is the real threat, that is a specialist conversation about topical options, not a home count of leftover chips. MedlinePlus is a fair public start. Cheap is not a reason to skip those two holds.
The itch got worse the night after day 1. Did the tablets fail?
Often the opposite, or at least not a failure yet. Dying mites and a bored immune system can flare for days. Post-scabetic itch can last two to four weeks after the last live mite is gone. New burrows after day 8, or a roommate who never treated, is the failure pattern. Antihistamines and a bland emollient are the usual comfort. Fainting, new confusion, trouble breathing, or a fever that looks like sepsis is not 'a strong itch.' That is a same-day clinic or emergency visit. Keep the day-8 swallow unless your own clinician stops the card.
Which medicines on my list should I read out before day 1?
All of them, but I listen hardest for chronic azoles, some macrolides, and anything that blocks P-glycoprotein. CYP3A4 is the main breakdown path. A strong inhibitor can lift levels; we still do not invent extra chips, and we still follow the meal-or-fast rule that matches the mark. Warfarin is the quiet one - I like an INR a few days after each swallow. Grapefruit in bulk is the folk CYP3A4 story. A fatty meal is an interaction even if it is not a 'drug,' especially if someone then adds a homemade third date because the itch lingered.
The internet still says ivermectin wipes out COVID. Why are you writing a mite card?
Because the labeled job is a nematode, and the mite card is an off-label two-date habit with a weight band. Dish work that 'killed virus' needed concentrations no safe human 3 mg swallow reaches. Large randomized COVID trials then looked for fewer hospital days, faster recovery, or fewer deaths and did not find a benefit that earns a virus row. People who then used horse paste met a concentration meant for a much heavier animal. FDA and MedlinePlus say the same thing in public English. If you have COVID, ask your own clinician about treatments that actually have outcome data. Do not spend a scabies 20-count on a cough.
If the mark is Strongyloides, do I still use day 1 and day 8?
No. Intestinal strongyloidiasis on the US label is a single oral dose at about 200 mcg/kg, fasting, then stool checks to prove the larvae are gone. Additional doses are generally unnecessary, but follow-up stools are not optional. Many of us still repeat near two weeks when autoinfection or a fragile host is in play - that is judgment, not a mite calendar. Oncho is a 150 mcg/kg swallow with a 3-to-12-month clock because adults live in nodules. The parasite map is the reading version of that fork. Do not paste a scabies card onto a named worm.
My cousin wants leftover 3 mg chips for 'prevention.' What do I say?
Say no. Leftover chips belong to a named person, a written kilogram, and two dates. Prevention stories - COVID, 'general parasites,' a trip with no stool and no skin exam - skip the mark. Sharing also skips pregnancy and Loa questions you cannot see. If your cousin has a real exposure, they need their own clinician and their own count. This desk will not bless a kitchen-table transfer. Cheap Stromectol 3 mg is still a prescription molecule in Portland.
Why do tropical programs treat this tablet like a public utility?
Because repeated community swallows crushed Onchocerca microfilariae hard enough that several regions could talk about eliminating river blindness, a disease that used to blind people who lived along fast rivers. Merck's 1987 Mectizan pledge made the tablet free for that use. The 2015 Nobel for Omura and Campbell is the prize version of the same soil-to-clinic story. WHO still writes the program language. A utility in a village round is still a prescription molecule on a Portland mite card. The donation does not make a farm syringe legal, and it does not put scabies on the FDA row.
Where did the 3 mg x 20 table come from, and can I click a coupon in the row?
The table is a teaching map of four licensed counters that actually run pharmacies - Costco, Walgreens, Target, Kroger. Each link opens that chain only. We did not invent a dollar for a count we could not quote live, so the cells stay qualitative. GoodRx's public 3 mg x 20 snapshot (retail near $70, coupon near $32) lives in the caption on purpose. Coupon sites are never a row href. This Portland desk still does not fill. Ask the window that will count the chips, and ask your own clinician whether day 1 and day 8 at 200 mcg/kg is even the card they meant.
General education from a clinician, not personal medical advice. Bring your own history to your own prescriber.
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