Cryptosporidiosis Medication

Updated: Jan 13, 2022
  • Author: Maria A Caravedo, MD; Chief Editor: Michael Stuart Bronze, MD  more...
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Medication Summary

Supportive therapy is the key component in the management of cryptosporidiosis. Replacement of fluids and electrolytes is the critically important first step in the management of this diarrheal illness. Oral rehydration is the preferred mode, but severely ill patients may require parenteral fluids.

Nitazoxanide, paromomycin, and azithromycin have activity against Cryptosporidium. [1]  A 3-day course of nitazoxanide oral suspension has been approved by the FDA for the treatment of cryptosporidiosis-related diarrhea in adults and in children older than 12 months who do not have HIV infection. In patients with AIDS, antiretroviral treatment has been associated with improvement, possibly because of general improvement of immune function. [61]  Paromomycin alone or with azithromycin is minimally effective (although paromomycin has been found to improve symptoms but rarely eradicates parasites) but may facilitate improvement in response to antiretroviral therapy. In solid organ transplant recipients, studies have shown that the heterogeneity of its prevalence varies by type of immunosuppression. In renal transplant recipients, for example, cyclosporine-based regimens were associated with a lower incidence of Cryptosporidium infections than tacrolimus-based regimens. [63]  Treatment may require prolonged courses of nitazoxanide or combination therapy plus reduction of immunosuppression. [43]  Mofetil mycophenolate may affect Cryptosporidium by inhibiting folate metabolism, although this theory has not been confirmed.

Several novel compounds are being developed with efficacy in animal models. [59]  However, none have documented efficacy in clinical trials.




Class Summary

Nitazoxanide is the only FDA-approved treatment for cryptosporidiosis in HIV-negative children and adults. Antiparasitic drugs may be used as an adjunct to therapy in patients with AIDS or organ transplant recipients undergoing immunosuppression. However, the mainstay of therapy is reversal of immunosuppression by antiretroviral drugs in AIDS or reduction of immunosuppressants in transplant recipients.

Nitazoxanide (Alinia)

Nitazoxanide inhibits the growth of Cryptosporidium parvum and Giardia lamblia trophozoites. It elicits antiprotozoal activity by interfering with pyruvate-ferredoxin oxidoreductase (PFOR) enzyme–dependent electron transfer reaction, which is essential to anaerobic energy metabolism. Nitazoxanide is the only medication approved by the FDA for the treatment for cryptosporidiosis in adults and children older than 12 months. It is administered in a 3-day, twice-daily course of tablets or oral suspension.


Paromomycin is an oral, nonabsorbed aminoglycoside that is partially active in cryptosporidiosis. An amebicidal and antibacterial agent, it is obtained from a strain of Streptomyces rimosus that is active in intestinal amebiasis.

Paromomycin has been used in patients who have AIDS and cryptosporidiosis; it was reported to cause symptomatic improvement but rarely parasite eradication. It has also been used for intestinal tapeworms.

Azithromycin (Zithromax, Zmax)

Azithromycin is a macrolide antibiotic. In a clinical study, it provided good symptom control in combination with paromomycin.


Antidiarrheal Agents

Class Summary

These agents are used to decrease the frequency of diarrheal stools and possibly the duration of episodes.

Loperamide hydrochloride (Imodium, Diamode)

This agent has an antimotility effect on the GI tract via cholinergic and opiate receptors. It is the first choice as an antidiarrheal agent. Loperamide hydrochloride has a more potent effect than diphenoxylate hydrochloride or codeine. It acts on intestinal muscles to inhibit peristalsis and slow intestinal motility. The drug prolongs the movement of electrolytes and fluid through bowel, increases viscosity, and decreases the loss of fluids and electrolytes.

Diphenoxylate and atropine (Lomotil)

The drug combination consists of diphenoxylate, which is an opiate constipating meperidine congener, and atropine, which an anticholinergic drug that inhibits excessive GI propulsion and motility.


The opiate anhydrous morphine, which is contained in paregoric, can decrease motility more than loperamide or the combination of diphenoxylate and atropine can.

Bismuth subsalicylate (Pepto-Bismol, Bismatrol, Kaopectate)

This agent exerts antisecretory and antibacterial effects to control diarrhea.


Attapulgite is an adsorbent and protectant that controls diarrhea.


Somatostatin Analogues

Class Summary

These agents inhibit the secretion of hormones involved in vasodilation. Octreotide (Sandostatin) may help, but no solid data show superiority over other antimotility agents. Cost and need for intravenous administration are the main factors that limit its use to only severe diarrheal cases.

Octreotide (Sandostatin)

Octreotide primarily acts on somatostatin receptor subtypes II and V. It inhibits growth hormone secretion and has a multitude of other endocrine and nonendocrine effects, including inhibition of glucagon, vasoactive intestinal peptide (VIP), and GI peptides.