Why lock two tablets to 26-44 kg when my cousin at 70 kg also took 'a couple'?
Knock: the scale talks before the bottle
The hold on OP-01 is two 3 mg chips for a 26-44 kg onchocerciasis band. Everything else hangs off that pair.
Weight decides the chip count on Stromectol. A 3 mg tablet is the only oral strength this card charts. When the scale sits between 26 and 44 kg and the job is onchocerciasis, the labeled pair is two chips - roughly 150 mcg/kg. I do not open a conversation with a brand slogan. I open with kilograms.
Two 3 mg Stromectol tablets equal six milligrams in the gut. That is a single oral event, not a week of swallows. Mass programmes often space retreatments by a year; an individual ward may come back as soon as three months if the skin still carries microfilariae. Adult worms in nodules keep laying. The chips clear the circulating young, not the factory.
This Dublin floor at 12 Merrion Square North reads cards. It does not hand out bottles. Dr. Saoirse Byrne signs the teaching line. Your own clinician writes the chart. If someone offers a cart instead of a kilogram, they have left the method: Knock, Chart, Ward-round, Sign-out.
Stools after Strongyloides, skin after oncho
Strongyloides clearance needs repeated stools, not a vibe. At least two exams at three to four weeks defined cure in the comparative studies. A French non-endemic series saw larvae return as late as day 106, so three months of checks is the cautious desk. Baermann concentration matters because the larval count per gram can be tiny.
Immunocompromised guts may need extra courses two weeks apart, and cure may still slip. Extra-intestinal Strongyloides is hard to stamp out; monthly suppression is sometimes the honest plan. HIV rooms taught that. A single pretty dose is not a promise in those hosts.
Oncho follow-up is skin and eye, plus the reminder that adults live on. Nodulectomy is old-fashioned and still logical when a nodule is findable. If the reader only wanted a cheap count, they will hate this paragraph. The count without the follow-up is how programmes lose years of work.
Why a worm channel is not a human one
Chemistry as consequence, not a puzzle. The 3 mg chip is the only oral unit this room charts.
| Mark on the card | What the label actually says |
|---|---|
| Family | Semisynthetic avermectin from Streptomyces avermitilis |
| Mix | Mostly H2B1a; smaller H2B1b share |
| Oral form here | 3 mg tablet only |
| Human brain | Does not readily cross the barrier at labeled doses |
| Adult Onchocerca | No activity; nodules can still shed |
Glutamate-gated chloride channels sit in invertebrate nerve and muscle. Ivermectin opens them, chloride floods in, the cell hyperpolarizes, and the parasite seizes up. That is the knock on the worm, not a pep talk for a virus. Avermectins also nibble GABA-gated chloride channels in some invertebrates. The useful part is still the glutamate gate.
Mammals lack those channels in the same places, and the drug has poor affinity for our ligand-gated chloride receptors. P-glycoprotein also keeps most of a labeled dose out of the brain. That is why a correctly weighted human tablet is usually quiet in the person and loud in the parasite. Overwhelm the pump with a livestock concentrate and that quiet ends.
Adult Onchocerca nodules keep making microfilariae after the chips. Ivermectin does not kill the adult. Skin counts in the registration work dropped about 83 percent by day three and about 99.5 percent by month three after 150 mcg/kg, and a greater than 90 percent reduction held toward a year. You still plan follow-up because the factory is alive.
Intestinal Strongyloides is a different stage problem. Activity is on the gut forms. Cure in the comparative work was absence of larvae on at least two stools three to four weeks later. Single 170-200 mcg/kg doses beat albendazole 200 mg twice daily for three days in those trials and matched thiabendazole 25 mg/kg twice daily for three days with fewer gut complaints.
Ward-round: Loa loa first, then the Mazzotti itch
Ward flags I say out loud
- West or Central Africa exposure - check loiasis before any ivermectin job
- Oncho Mazzotti - itch, fever, tender nodes, postural dizziness after dying microfilariae
- Sowda - more edema and skin flare than a plain oncho room
- Hypersensitivity to a tablet component - the only formal contraindication
Heavily infected Loa loa carriers can drop into encephalopathy after a microfilaricide - neck and back pain, red eye, conjunctival bleed, incontinence, inability to stand, confusion, seizure, coma. It is rare after ivermectin and it is not a trivia line. Anyone with real West or Central African exposure needs a loiasis look before the chips, then a watched recovery.
Mazzotti itching and fever mean dying Onchocerca microfilariae, not a failed tablet. DEC taught that lesson decades ago. Hydration, lying flat, saline, and sometimes parenteral steroid have been used for postural drops. Milder rooms get antihistamine or aspirin. Sowda skin can swell harder than a plain oncho rash.
Sowda skin can flare harder after a microfilaricide. Tell the reader that before they swallow, or they will think the chips poisoned them. Anterior chamber microfilariae can tick up at day three, then fall by months three and six versus placebo in the controlled work. That eye line is follow-up, not a reason to skip a labeled oncho dose.
Warfarin has a thin post-marketing INR rise signal. I do not call it a daily interaction, and I do not ignore a climbing INR after a dose. Pregnancy lacks adequate human trials; animal clefts showed up near maternotoxic doses. Milk carries low amounts. Under 15 kg, safety is not established. Those are holds, not slogans.
Does a Dublin clinic list Stromectol 3 mg as a cart?
| Pharmacy | Strength / count | How the window works | Official page |
|---|---|---|---|
| CVS | 3 mg x 10 | Ordinary cash counter | CVS pharmacy |
| Walmart | 3 mg x 10 | Ordinary cash counter | Walmart pharmacy |
| Harris Teeter | 3 mg x 10 | Kroger-family pharmacy desk | Harris Teeter pharmacy |
| Costco | 3 mg x 10 | Warehouse pharmacy; membership may apply | Costco pharmacy |
Nobody on Merrion Square sells a Stromectol basket. A pastel room card is teaching. The window that counts tablets sits at a licensed US pharmacy, and even there the clerk needs a prescription and a weight. If a page pretends this institute is a checkout, close it.
Four licensed US counters publish a 3 mg by ten generic count in the fill strip below. Those rows name the chain and open that chain only. GoodRx and SingleCare stay in the caption. This clinic does not fill. Prices move by ZIP, and I will not invent a euro figure for a Dublin desk that never dispenses.
A cart implies a checkout we do not run. What we do run is the lock: two chips when onchocerciasis meets 26-44 kg. If your scale sits elsewhere, the table in the next room changes the count. Do not borrow a neighbour's band because the tablet looks the same.
Empty plate: fat multiplies the number you thought you gave
Absorption
Oral, roughly dose-proportional in the studied range; high-fat meal ~2.5-fold higher bioavailability. Fasted water is the labeled clock.
Distribution
Lipophilic; stays out of brain at labeled human doses because of P-glycoprotein and low mammalian channel affinity.
Metabolism
Mainly CYP3A4 in liver microsomes; CYP2D6 and CYP2E1 are minor in vitro players. Labeled concentrations did not meaningfully inhibit those CYPs.
Excretion
Faeces over ~12 days; urine <1%. Plasma half-life ~18 hours.
Fasted-room marks
PlateEmpty, water only
Fat meal~2.5× exposure
Tmax~4 hours after 12 mg fasted
Half-life~18 hours
Urine<1% of the dose
High-fat breakfasts roughly two-point-five times the amount that reaches blood. The label study used 30 mg after a 48.6 g fat meal versus the same 30 mg fasted. That is not a cooking tip. It is why Stromectol is taken on an empty stomach with water. The registration counts assumed that plate.
Registration work used empty-stomach conditions for the doses that later became the weight tables. Eat a greasy plate and you are no longer in the exposure the tables assume. I would rather a slightly lower, predictable level than a surprise spike in someone I have not examined.
Peak levels land around four hours after a fasted 12 mg dose in volunteers, with mean H2B1a concentrations in the 30-47 ng/mL band and a wide range under that mean. Half-life is about 18 hours. Almost all of the dose leaves in faeces over roughly twelve days. Urine sees less than 1 percent.
Three platform trials, then WHO's outside-trial hold
1970s
Avermectins isolated from Streptomyces avermitilis. Satoshi Omura and William Campbell later shared the 2015 Nobel for that river-blindness line.
1996
US Stromectol tablet for intestinal Strongyloides and onchocerciasis. Oral unit: 3 mg.
2022
TOGETHER, then ACTIV-6 and PRINCIPLE: no meaningful COVID benefit at studied outpatient courses.
Now
WHO: not for COVID outside trials. This room agrees.
TOGETHER sent outpatients a three-day ivermectin course and did not cut hospitalization or prolonged emergency observation versus placebo. That 2022 outpatient result is the one I quote when a cousin 'got better on it.' Most people with COVID get better on tea as well. Platforms exist so we stop arguing from cousins.
ACTIV-6 and PRINCIPLE reached the same empty clinical place. Recovery clocks and hospitalization marks did not move in a way a ward would spend a tablet on. Dish concentrations that nicked SARS-CoV-2 sat far above what a labeled human dose puts in blood. Biology and the platforms agree.
WHO keeps COVID use inside trials. FDA never authorized the tablet for prevention or treatment of that virus. Stretching a superb antiparasitic into an antiviral was a category error, then a supply error, then a paste error. The evidence study walks the protocols without turning this card into a press fight.
Human chips only - paste is a different object
Veterinary paste is formulated for a horse, not a 26-44 kg person. The molecule can match. The concentration, excipients, and measuring spoon do not. People who treated themselves from a tube during the viral years overshot into drowsiness, confusion, vomiting, and sometimes seizures because they drowned the brain pump.
Human Stromectol chips are counted in threes of milligrams. A 26-44 kg oncho pair is two chips. A Strongyloides card uses the other grid. That is the entire dosing conversation on this floor. I will not convert a livestock syringe into a human milligram. If the indication is real, the tablet comes from a pharmacy.
Scabies and some other mite or worm jobs sit off this US label. Off-label is a specialist sentence, not a cart sentence. When a second dose appears in those rooms, it is usually about eggs hatching after the first kill, not about the first chips 'failing.' Do not invent a 6 mg or 12 mg human tablet. The oral unit is 3 mg.
Chart: two tables, one 3 mg chip
| Job on the card | Target | 26-44 kg count | Empty plate |
|---|---|---|---|
| Onchocerciasis | ~150 mcg/kg | 2 × 3 mg | Water, no meal |
| Strongyloidiasis | ~200 mcg/kg | 2 chips if 25-35 kg; 3 if 36-50 kg | Water, no meal |
| Scale under 15 kg | Not established | Do not invent a half-chip | Specialist first |
Chart the parasite before you count chips. Onchocerciasis dosing aims near 150 mcg/kg. Strongyloidiasis aims near 200 mcg/kg. Both use the same 3 mg tablet. The bands are not twins. A 30 kg reader is two chips for river blindness and still two chips for Strongyloides. A 40 kg reader stays on two for oncho and jumps to three for Strongyloides.
Strongyloides wants roughly two hundred micrograms per kilogram. Label bands for that job run 15-24 kg as one tablet, 25-35 as two, 36-50 as three, then four, then five, then calculate once the scale crosses 80 kg. That is why a 26-44 kg oncho pair must not be copied onto a Strongyloides card without looking at the second table.
Same white 3 mg chip, two jobs. Oncho bands: 15-25 kg one tablet, 26-44 two, 45-64 three, 65-84 four, then 150 mcg/kg at 85 kg and above. I keep both grids on the desk because residents mix them under time pressure. Mixing them is the most common counting error I see.
Mass campaigns often retreat every twelve months. Individual patients can be retreated from three months if the skin load returns. Strongyloides usually wants one correctly weighted dose, then stool proof, not a second guess the next morning. Immunocompromised guts are the exception that needs a longer plan.
Sign-out from the 26-44 kg room
Sign-out on this card is two 3 mg chips for 26-44 kg onchocerciasis, fasted water, a Loa loa question if the map says West or Central Africa, and a second table if the worm is Strongyloides. Human tablets. No COVID role outside a trial. No paste.
Bring kilograms and the named parasite to your own clinician before anyone changes a dose. This Merrion Square room teaches. It does not examine you. The live FDA label still wins if a sentence here ages.
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Consulting room questions
Answered by Dr. Saoirse Byrne, MD · Internal medicine & clinical pharmacology
Mail on OP-01 still arrives as if Merrion Square were a checkout. It is not. I answer the way I would on a ward-round: kilograms, parasite, empty plate, Loa loa, human chips. Teaching only. Your own clinician writes the chart.
Because the onchocerciasis table is a set of bands, not a vibe. Twenty-six to forty-four kilograms is two 3 mg chips, about 150 mcg/kg. Sixty-five to eighty-four kilograms is four chips. A cousin who swallowed 'a couple' at 70 kg under-dosed the job or was not on an oncho card at all. I chart the scale and the parasite, then I count. I do not copy a family story.
If I have Strongyloides and I weigh 40 kg, do I still take two chips?
No. Forty kilograms on the Strongyloides grid is three 3 mg tablets, because that job aims near 200 mcg/kg and the 36-50 kg band is three chips. Two chips at 40 kg is the onchocerciasis pair, not the Strongyloides pair. Same tablet, different table. That mix-up is the one I correct most often on this floor. Empty stomach with water either way.
Does a Dublin clinic list Stromectol 3 mg as a cart I can click?
No. Oracel is a reading clinic at 12 Merrion Square North. We do not list a basket and we do not ship chips. The fill strip on the card names four licensed US counters for a generic 3 mg by ten so you can see how a real window talks. Each link opens that chain only. If you need the medicine, your own prescriber and a pharmacy do the work. We stay on the teaching side.
I ate sausages then took the tablets. Did I ruin the dose?
You changed the exposure. A high-fat meal in the label study - 48.6 grams of fat - lifted bioavailability about two and a half times versus fasted 30 mg. The weight tables assume an empty plate and water. I would not invent a 'catch-up' extra chip the same morning. I would tell your prescriber what you ate and when, then watch for more dizziness or itch than expected and keep the follow-up stools or skin checks on time.
We lived in Cameroon for a year. Why is everyone suddenly talking about Loa loa?
Because a heavy Loa loa load plus a drug that kills microfilariae can trigger a rare, sometimes fatal encephalopathy - pain, red eye, incontinence, confusion, seizure, coma. It has been seen after ivermectin, rarely. West and Central Africa are the map. If you have a real reason for the tablet, the desk should look for loiasis first and watch you after. That is not theatre. It is the one hold I will not shrug off for a 'simple deworm.'
The itch and fever after river-blindness treatment scared my mother. Failure?
Usually the opposite. Mazzotti is the immune noise from dying microfilariae - itch, fever, tender nodes, aches, sometimes a postural dip. DEC taught the name. Hydration and lying flat handle many rooms; antihistamine or aspirin for the milder ones; saline or steroid if the blood pressure drops. Tell her before the chips so she does not decide the medicine 'poisoned' a successful kill. Severe or odd neurology is a different door - that is when I think Loa loa and the emergency ward, not a simple Mazzotti.
Horse paste is cheaper. Is the molecule not the same?
The molecule can be the same and the object is still wrong. Paste is built for a large animal. You cannot measure two human 3 mg chips from a tube with any honesty. People who tried that during the viral years overdosed into confusion and vomiting because they swamped the pump that keeps the drug out of the brain. Human tablets, pharmacy count, named parasite. I will not help anyone convert a syringe.
My brother took it for COVID and was fine in five days. Why do you shut that door?
Most people with COVID are fine in five days on toast. TOGETHER gave outpatients a three-day course and did not reduce hospitalization or long emergency stays versus placebo. ACTIV-6 and PRINCIPLE also failed to show a clinical win a ward would spend a tablet on. WHO says keep COVID use inside trials. FDA never labeled the tablet for that virus. A brother's recovery is a story. Platforms are how we stop treating stories as doses.
Do I need a second Strongyloides dose if I already feel well?
Feeling well is not a stool. The labeled job is usually one correctly weighted dose, then exams to prove the larvae are gone. Recrudescence showed up months later in a non-endemic series, so the desk keeps checking. Immunocompromised readers may need repeats at two-week gaps and may never get a tidy cure. Do not add a second dose because a forum said always double. Add it because your clinician has a host or a positive stool that justifies it.
I take warfarin. Is a one-day Stromectol course a problem?
There is a rare post-marketing signal of a higher INR when the two sit together. It is not a daily CYP story like some antibiotics. I would still tell the clinician who owns your INR and check sooner after the chips if you are in a tight range. I would not skip a needed antiparasitic on a rumour, and I would not ignore a climbing INR after the dose. That is the whole warfarin paragraph on this card.
Can I give a 3 mg chip to a 12 kg child?
Safety and effectiveness under 15 kg are not established on the US tablet label. I do not split a chip into a homemade paediatric dose on a pastel card. If a small child truly needs an antiparasitic, that is a specialist room with a different risk conversation, not a Dublin teaching strip. Pregnancy is also a hold unless the infection outweighs the missing human data. Animal clefts appeared near doses that already hurt the mother.
Why does oncho need follow-up if the skin counts crash so hard?
Because adults in nodules keep shedding. The chips are microfilaricidal. Skin counts fell hard by day three and stayed down toward a year in the controlled work, which is impressive and still not a sterilizing cure. Programmes retreat. Individuals may retreat from three months. Eyes need a look because anterior chamber counts can tick before they fall. A crash on a skin snip is a good morning. It is not a closed file.
I have kidney disease. Does my Stromectol count change like gabapentin would?
Urine sees less than one percent of an ivermectin dose. Faeces carry almost all of it over about twelve days. I do not cut the 26-44 kg oncho pair for a high creatinine the way I cut Neurontin. Liver and CYP3A4 matter more. Strong inhibitors can lift levels; inducers can blunt them. Still tell the prescriber about the kidneys, because the rest of your chart may change. The tablet itself is not a renal-adjust drug.
Read these as teaching on a general point, not as a care plan for whoever asked. Anything specific to you belongs with a prescriber who can see your notes, bloods and full medicine list at once.