Dawaa Reference

chronic

Loiasis (Loa Loa Infection)

Treatment options, dosing, cautions and Egyptian brands from the shipped Dawaa Reference card.

Evidence status

Checked against the sources named below

Sources3 sources

Filariasis - StatPearls - NCBI Bookshelf - https://www.ncbi.nlm.nih.gov/books/NBK556012/ · ICPC-3 (WONCA International Classification of Primary Care, 3rd edition) class AD24.07 - condition scope only, no dose · Egyptian National Drug Formulary - Antimicrobial 2023 (diethylcarbamazine monograph, p28)

Verified against2 documents
  • Loiasis (Loa Loa Infection) - disease-level clinical article (loiasis-clinical.txt)
  • Egyptian National Drug Formulary - Antimicrobial 2023 (diethylcarbamazine monograph, p28)

Verified date2026-08

Presentation reference

Is it this?

Reference only, to read alongside your own examination.

Symptoms — what the patient reports (5)

  • Most people infected with Loa loa have no symptoms at all
  • Transient, non-red swellings under the skin (Calabar swellings) occur on the face or limbs from a hypersensitivity reaction to the moving worm
  • Pain, itching, or hives can come before a Calabar swelling appears, and the swelling usually settles within 2 to 4 days [itching · urticaria]
  • Patients sometimes notice a worm crossing under the conjunctiva of the eye, with brief swelling and inflammation
  • Calabar swellings sit most often near a joint, and they are a hypersensitivity reaction to the worm moving, not the worm itself

Signs — what you find (2)

  • Eye symptoms typically settle once the worm has migrated out, and crossing the conjunctiva usually takes 10 to 20 minutes
  • Less common complications include joint inflammation, heart muscle fibrosis, and brain/meninges involvement

Tests (5)

  • Marked eosinophilia, often above 3000 cells/uL, and raised IgE are common lab findings in filarial infection
  • For L. loa, blood is best drawn between 10 am and 2 pm because its microfilariae circulate by day
  • An antibody test against the recombinant LLSXP-1 antigen is L. loa specific but is currently research-only
  • Heavy L. loa microfilaraemia can give a false-positive circulating antigen test intended for W. bancrofti
  • Diagnosis rests on finding a migrating adult worm under the skin or conjunctiva, or microfilariae in the blood

If not this — what else fits (8)

  • Bacterial lymphangitis
  • Cutaneous larva migrans
  • Gnathostomiasis
  • Idiopathic hypereosinophilic syndrome
  • Strongyloidiasis
  • Systemic vasculitis
  • Other zoonotic filarial infections such as Dipetalonema
  • Tuberculosis

SourceStatPearls "Filariasis" - disease-level clinical article

Presentation findings are traced to the source above.

Rx: Antiparasitic | Main treatment

ANTIPARASITIC

1

DIETHYLCARBAMAZINE

Antiparasitic

1st line

Strength100 mg

Formoral.solid

Adult dose and duration

8-10 mg/kg/day in 3 divided doses x 21 days; repeat courses may be needed for cure

Paediatric dose

8-10 mg/kg/day

(Children and adolescents: 8-10 mg/kg/day in 3 divided doses for 21 days, the same rule as for adults.)

Dose by weight
3kg24-30 mg/day
4kg32-40 mg/day
5kg40-50 mg/day
6kg48-60 mg/day
7kg56-70 mg/day
8kg64-80 mg/day
9kg72-90 mg/day
10kg80-100 mg/day
11kg88-110 mg/day
12kg96-120 mg/day
13kg104-130 mg/day
14kg112-140 mg/day
15kg120-150 mg/day
16kg128-160 mg/day
17kg136-170 mg/day
18kg144-180 mg/day
19kg152-190 mg/day
20kg160-200 mg/day
21kg168-210 mg/day
22kg176-220 mg/day
23kg184-230 mg/day
24kg192-240 mg/day
25kg200-250 mg/day
26kg208-260 mg/day
27kg216-270 mg/day
28kg224-280 mg/day
29kg232-290 mg/day
30kg240-300 mg/day
31kg248-310 mg/day
32kg256-320 mg/day
33kg264-330 mg/day
34kg272-340 mg/day
35kg280-350 mg/day
36kg288-360 mg/day
37kg296-370 mg/day
38kg304-380 mg/day
39kg312-390 mg/day
40kg320-400 mg/day
41kg328-410 mg/day
42kg336-420 mg/day
43kg344-430 mg/day
44kg352-440 mg/day
45kg360-450 mg/day
46kg368-460 mg/day
47kg376-470 mg/day
48kg384-480 mg/day
49kg392-490 mg/day
50kg400-500 mg/day
Dose source

Egyptian National Drug Formulary - Antimicrobial 2023 (diethylcarbamazine monograph, p28)

Why

The formulary names treatment and prophylaxis of loiasis as this drug's indication and gives the CDC regimen of 8-10 mg/kg/day in three divided doses for 21 days, for adults and for children alike. The disease article cited on the card gives the same figure and adds the reason it cannot simply be prescribed: in a patient carrying a heavy microfilarial load the drug can cause encephalitis and shock, so the blood microfilarial count decides the approach before the first tablet.

Cautions
  • COUNT THE MICROFILARIAE BEFORE TREATING. The cited article gives 8,000 microfilariae/mL as the threshold: below it, this regimen; above it, albendazole 200 mg twice daily for 21 days first to bring the load down, with apheresis for very high loads. Some experts set the threshold lower, at 2,500/mL, and use ivermectin 150 mcg/kg between 2,500 and 20,000.
  • CONTRAINDICATED IN ONCHOCERCIASIS - the formulary's only listed contraindication. Giving this drug to someone co-infected with river blindness triggers a severe inflammatory reaction.
  • FOR A PATIENT WITH MICROFILARIA IN THE BLOOD the formulary offers a dose-escalating start instead: 50 mg once on day 1; 50 mg three times on day 2; 100 mg three times on day 3; then 9 mg/kg/day in 3 divided doses from day 4 to the end.
  • Test for co-infection with onchocerciasis and with loiasis itself before treating anyone from an area where either is endemic. Both diethylcarbamazine and ivermectin can cause a fatal encephalopathy in loiasis.
  • Prophylaxis, where exposure continues, is 300 mg once weekly.
Egyptian brands

No Egyptian brand matched — prescribe by generic name.

MAIN TREATMENT

2

REFERRAL & SAFETY-NETTING (NO DRUG THERAPY)

1st line
Adult dose and duration

Filarial infection transmitted by the Chrysops fly of Central/West African forests, not found in Egypt. Relevant only in a patient with a matching travel history presenting with migrating (Calabar) swellings or a worm crossing the eye; treatment (diethylcarbamazine) can trigger severe reactions in heavily infected patients and needs specialist supervision. - Refer

Paediatric dose

Children follow the same pathway: recognise and refer. No primary-care medicine is implied.

Dose source

No dose - referral pathway, no medicine given in primary care

Why

Filarial infection transmitted by the Chrysops fly of Central/West African forests, not found in Egypt. Relevant only in a patient with a matching travel history presenting with migrating (Calabar) swellings or a worm crossing the eye; treatment (diethylcarbamazine) can trigger severe reactions in heavily infected patients and needs specialist supervision.

Cautions
  • Not endemic in Egypt. Relevant to a returning traveller or an imported case; consider the travel history before anything else.
  • The drug rows above are what the treating service gives. They are here so that the referral is an informed one and so the GP can recognise the regimen the patient comes back on - not as permission to start it without the referral.
  • RED FLAG - Both DEC and ivermectin can cause potentially fatal encephalopathy in patients with loiasis.
  • RED FLAG - A worm visibly crossing the conjunctiva, Calabar swellings after travel to Central or West Africa, or a very high microfilarial load before treatment, which carries a risk of encephalopathy with diethylcarbamazine and must be specialist-managed.

Prices are indicative (dataset snapshot 2026-06); verify with the pharmacy.