Dawaa Reference

infectious

Giardiasis

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

Evidence status

Checked against the sources named below

Sources4 sources

ALINIA (nitazoxanide) US prescribing information, section 2.1 Recommended Dosage, Table 1 (DailyMed SetID e90f98d9-3c9b-4e75-ba18-5517283eadf0) · WHO Parasitic Diseases 2021 · Egyptian National Drug Formulary - Antimicrobial 2023 (metronidazole monograph) · Tindamax (tinidazole) US prescribing information, Dosage and Administration - Giardiasis (DailyMed, Mission Pharmacal)

Verified against4 documents
  • Egyptian National Drug Formulary - Antimicrobial 2023 (metronidazole monograph)
  • Tindamax (tinidazole) US prescribing information, Dosage and Administration - Giardiasis (DailyMed, Mission Pharmacal)
  • ALINIA (nitazoxanide) US prescribing information, section 2.1 Recommended Dosage, Table 1 (DailyMed SetID e90f98d9-3c9b-4e75-ba18-5517283eadf0)
  • Giardiasis - disease-level clinical article (giardiasis-clinical.txt)

Verified date2026-08

Presentation reference

Is it this?

Reference only, to read alongside your own examination.

Symptoms — what the patient reports (12)

  • Diarrhea affects over 90% of symptomatic patients, with flatulence in about 75% and abdominal pain in about 78% [abdominal pain · diarrhoea · flatulence]
  • Vomiting occurs in about 40% and fever in about 27% of symptomatic cases, both less common than diarrhea [diarrhoea · fever · vomiting]
  • Bloody diarrhea is uncommon, occurring in under 12%, and should raise concern for another cause [bloody diarrhoea · diarrhoea]
  • Symptoms usually begin one to two weeks after exposure and may clear on their own within one to four weeks
  • Up to 40% of patients develop temporary lactose intolerance from gut lining damage
  • Extraintestinal features such as hives, painful urination, joint pain, or eye symptoms occur mainly in chronic cases [burning on passing urine · joint pain · urticaria]
  • The typical picture is bloating and abdominal distension alongside the diarrhoea, the flatulence and the pain [abdominal distension · diarrhoea · flatulence]
  • Carrying it with no symptoms at all is also common
  • In some patients it becomes chronic, and then it causes malabsorption and weight loss [weight loss]
  • It is one of the commonest treatable causes of gastroenteritis in the world, and the burden falls hardest on low-income countries
  • The organism is a protozoan parasite, Giardia duodenalis
  • In high-income countries the risks named are international travel, untreated freshwater, male-to-male sexual contact, contact with children in nappies, recent antibiotics, and existing chronic bowel disease

Signs — what you find (3)

  • Examination findings are usually unremarkable; dehydration signs may be present and fever is rarely seen [dehydration · fever]
  • Abdominal tenderness on palpation and increased bowel sounds (borborygmi) on auscultation may be found [abdominal tenderness]
  • Conjunctival redness or discharge, rash, or joint swelling may be seen on exam as extraintestinal signs [eye redness · joint swelling · rash]

Tests (4)

  • Stool microscopy for trophozoites or cysts is the traditional test, though newer methods are now preferred
  • Testing three stool samples collected over several days improves detection sensitivity
  • Stool antigen testing is about 92% sensitive, while PCR-based testing reaches up to 99%
  • Routine blood counts and electrolytes are usually normal, and eosinophilia is rarely seen

If not this — what else fits (4)

  • Cyclospora or Cystoisospora infection is on the differential for giardiasis
  • Irritable bowel syndrome is on the differential for giardiasis
  • Inflammatory bowel disease is on the differential for giardiasis
  • Viral gastroenteritis is on the differential for giardiasis

SourceStatPearls "Giardiasis" - disease-level clinical article

Presentation findings are traced to the source above.

1

METRONIDAZOLE

1st line

Strength250 mg

Formoral.solid

Adult dose and duration

250-500 mg TID for 5-7 days or single 2 g daily dose for 3 days x 3-7 days

Paediatric dose

15-30 mg/kg/day [child max 1200 mg] (Divided TID for 5-7 days)

Dose by weight
3kg45-90 mg/day
4kg60-120 mg/day
5kg75-150 mg/day
6kg90-180 mg/day
7kg105-210 mg/day
8kg120-240 mg/day
9kg135-270 mg/day
10kg150-300 mg/day
11kg165-330 mg/day
12kg180-360 mg/day
13kg195-390 mg/day
14kg210-420 mg/day
15kg225-450 mg/day
16kg240-480 mg/day
17kg255-510 mg/day
18kg270-540 mg/day
19kg285-570 mg/day
20kg300-600 mg/day
21kg315-630 mg/day
22kg330-660 mg/day
23kg345-690 mg/day
24kg360-720 mg/day
25kg375-750 mg/day
26kg390-780 mg/day
27kg405-810 mg/day
28kg420-840 mg/day
29kg435-870 mg/day
30kg450-900 mg/day
31kg465-930 mg/day
32kg480-960 mg/day
33kg495-990 mg/day
34kg510-1020 mg/day
35kg525-1050 mg/day
36kg540-1080 mg/day
37kg555-1110 mg/day
38kg570-1140 mg/day
39kg585-1170 mg/day
40kg600-1200 mg/day
41kg615-1200 mg/day (upper capped)
42kg630-1200 mg/day (upper capped)
43kg645-1200 mg/day (upper capped)
44kg660-1200 mg/day (upper capped)
45kg675-1200 mg/day (upper capped)
46kg690-1200 mg/day (upper capped)
47kg705-1200 mg/day (upper capped)
48kg720-1200 mg/day (upper capped)
49kg735-1200 mg/day (upper capped)
50kg750-1200 mg/day (upper capped)
Dose source

Egyptian National Drug Formulary - Antimicrobial 2023 (metronidazole monograph)

Why

Nitroimidazole antiprotozoal that is activated inside the parasite to damage its DNA; the standard, inexpensive first-line treatment for giardiasis.

Cautions
  • Avoid alcohol completely during treatment.
  • Treat all household contacts if symptomatic.
  • Nausea and metallic taste are common.
Egyptian brands
Egyptian brandManufacturerIndicative price
TRICHOGYL 250 MG 20 TAB.EL NASR4.35 EGP (0.22/unit)
FLAGICURE 250MG 20 TAB.KAHIRA7.00 EGP (0.35/unit)
TRICHOCID 250MG 20 TAB.CID7.00 EGP (0.35/unit)
METRONIDAZOLE-MUP 250 MG 20 F.C. TABS.MUP11.00 EGP (0.55/unit)
AMRIZOLE 250 MG 20 TABS.AMRIYA20.00 EGP (1.00/unit)
METROZOLE 250MG 20 TAB.MEMPHIS20.00 EGP (1.00/unit)
DUMOZOL 125MG/5ML SUSP. 125ML? strength differs? different route - not oral solidMINA PHARM > ALPHARMA-DENMARK5.75 EGP
METROZOLE 125MG/5ML SUSP. 120 ML? strength differs? different route - not oral solidMEMPHIS19.50 EGP
2

TINIDAZOLE

1st line

Strength500 mg

Formoral.solid

Adult dose and duration

2 g single dose taken with food - single-dose

Paediatric dose

50 mg/kg/dose [child max 2000 mg] (Single dose with food)

Age restriction: minimum 36 months

Dose by weight
3kg150 mg/dose
4kg200 mg/dose
5kg250 mg/dose
6kg300 mg/dose
7kg350 mg/dose
8kg400 mg/dose
9kg450 mg/dose
10kg500 mg/dose
11kg550 mg/dose
12kg600 mg/dose
13kg650 mg/dose
14kg700 mg/dose
15kg750 mg/dose
16kg800 mg/dose
17kg850 mg/dose
18kg900 mg/dose
19kg950 mg/dose
20kg1000 mg/dose
21kg1050 mg/dose
22kg1100 mg/dose
23kg1150 mg/dose
24kg1200 mg/dose
25kg1250 mg/dose
26kg1300 mg/dose
27kg1350 mg/dose
28kg1400 mg/dose
29kg1450 mg/dose
30kg1500 mg/dose
31kg1550 mg/dose
32kg1600 mg/dose
33kg1650 mg/dose
34kg1700 mg/dose
35kg1750 mg/dose
36kg1800 mg/dose
37kg1850 mg/dose
38kg1900 mg/dose
39kg1950 mg/dose
40kg2000 mg/dose
41kg2000 mg/dose (capped)
42kg2000 mg/dose (capped)
43kg2000 mg/dose (capped)
44kg2000 mg/dose (capped)
45kg2000 mg/dose (capped)
46kg2000 mg/dose (capped)
47kg2000 mg/dose (capped)
48kg2000 mg/dose (capped)
49kg2000 mg/dose (capped)
50kg2000 mg/dose (capped)
Choice

The source names tinidazole as the most effective agent for giardiasis, with nitazoxanide as the alternative.

Dose source

Tindamax (tinidazole) US prescribing information, Dosage and Administration - Giardiasis (DailyMed, Mission Pharmacal)

Why

Nitroimidazole in the same class as metronidazole but with a longer half-life allowing a shorter course, offered as an alternative for patients wanting a simpler regimen.

Cautions
  • Avoid alcohol during and for 3 days after dose.
  • Take with food.
  • The label licenses the paediatric single dose from 3 years, not below.
  • Not in the first trimester of pregnancy. Later in pregnancy weigh it case by case, and stop breastfeeding for the dose and 3 days after - it stays in milk that long.
Egyptian brands
Egyptian brandManufacturerIndicative price
FASIGYN 500 MG 4 TABS.PFIZER8.35 EGP (2.09/unit)
PROTOZOLE 500 MG 12 F.C.TABS.MUP39.00 EGP (3.25/unit)
3

NITAZOXANIDE

1st line

Strength500 mg

Formoral.solid

Adult dose and duration

500 mg BID with food x 3 days

Paediatric dose

(100 mg BID (1-3 yrs) or 200 mg BID (4-11 yrs) with food for 3 days)

Dose by age
1 to 3 years:100 mg twice daily with food, for 3 days
4 to 11 years:200 mg twice daily with food, for 3 days
Dose source

ALINIA (nitazoxanide) US prescribing information, section 2.1 Recommended Dosage, Table 1 (DailyMed SetID e90f98d9-3c9b-4e75-ba18-5517283eadf0)

Why

Antiprotozoal that interferes with the parasite's electron transfer enzyme system; a useful alternative to the nitroimidazoles, particularly convenient in Egypt where it is available as a paediatric suspension.

Cautions
  • Take with food.
  • Nitazoxanide is an excellent pediatric option available as suspension in Egypt.
  • Urine discoloration can occur.
Egyptian brands
Egyptian brandManufacturerIndicative price
UNINITAPROZAX 500MG 12 F.C. TAB.UNIPHARMA CO. > UNIPHARMA16.00 EGP (1.33/unit)
CRYPTOPER 500MG 30 F.C. TAB.EGPI > TAG PHARMA56.00 EGP (1.87/unit)
XEROVIRINC 500MG 18 F.C. TAB.MINA PHARM42.00 EGP (2.33/unit)
PARAZOXANIDE 500 MG 18 CAP.MISR > PHARMACARE63.00 EGP (3.50/unit)
TRUSTNAL 500 MG 10 F.C. TABS.ADWIA40.00 EGP (4.00/unit)
NIT CLEAN 500MG 12 F.C. TABS.WESTERN PHARMACEUTICALS INDUSTRIES > WESTERN PHARMA72.00 EGP (6.00/unit)
CRYPTONAZ 500MG 12 F.C.TAB.COPAD PHARMA82.00 EGP (6.83/unit)
NIT CLEAN 500MG 5*6 F.C. TABS.WESTERN PHARMACEUTICALS INDUSTRIES > WESTERN PHARMA180.00 EGP (30.00/unit)
UNINITAPROZAX 100MG/5ML SUSP. 60ML? strength differs? different route - not oral solidUNIPHARMA CO. > UNIPHARMA6.00 EGP
ZOLIFUTAL 100MG/5ML SUSP. 60 ML? strength differs? different route - not oral solidFUTURE PHARMACEUTICAL INDUSTRIES (FPI)13.50 EGP

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