Antimalarial drugs such as chloroquine are used to treat malaria. Chloroquine works by accumulating in the acidic food vacuoles of the plasmodium parasite and forming a toxic complex with heme that kills the parasite. Side effects include nausea, vomiting, headaches, and potentially irreversible retinopathy or ototoxicity with prolonged use. Nitroimidazole drugs like metronidazole are used to treat amoebiasis and other infections and can cause gastrointestinal side effects. Anthelmintic drugs treat helminth infections and examples include mebendazole, albendazole, and diethylcarbamazine, which can be used against filariasis.

1. Antimalarial
drugs

2.  Malaria – a protozoal infection - P.vivax, P.ovale
P.falciparum & P.malariae
Antimalarial drugs (examples) –
• Proguanil, Pyrimethamine
• Primaquine
• Chloroquine
• Mefloquine
• Quinine
• Artemisinin derivatives, Atovaquone
• Sulfadoxine, Doxycycline

3. Chloroquine:
MOA –
• Basic drug – taken up by the acidic food vacuoles of
susceptible plasmodia
• ‘Drug-heme’ complex – toxic & kills the parasite
Haemoglobin
heme (toxic)
hemozoin (non-toxic
to plasmodium)
heme polymeraseChloroquine

4. Uses:
Malaria
Hepatic amoebiasis
Lepra reaction
Rheumatoid arthritis
Infectious mononucleosis
Discoid lupus erythematosus

5. Adverse effects:
 Nausea, vomiting, headache
 Skin rashes, itching, visual disturbances
 Parenteral administration – hypotension, confusion,
cardiac arrhythmias &
convulsions
 Prolonged administration – irreversible
retinopathy
& ototoxicity
 Myopathy, cardiomyopathy, neuropathy &
psychiatric
disturbances

6. Anti-amoebic
drugs

7. Amoebiasis – a protozoal infection – Entamoeba
histolytica
Antiamoebic drugs (examples) -
• Nitroimidazoles – Metronidazole, Tinidazole
Secnidazole, Ornidazole
• Emetine , Dehydroemetine
• Chloroquine
• Diloxanide furoate
• Iodoquinol
• Tetracyclines, Paromomycin, Erythromycin

8. Uses of nitroimidazoles:
Amoebiasis
Trichomonas vaginitis
Giardiasis
Anaerobic infections
i. Anaerobic brain abscess
ii. Pseudomembranous colitis
iii. Vincent’s angina
iv. H.pylori infection
Guinea worm infestation

9. Adverse effects :
 Gastrointestinal – anorexia, nausea, metallic taste,
epigastric distress, abdominal cramps
 Allergic reactions – skin rashes, urticaria, itching &
flushing
 CNS – dizziness, vertigo, confusion, irritability,
headache & rarely convulsions
 Disulfiram-like reaction if taken with alcohol –
nausea, vomiting, abdominal cramps, headache &
flushing

10. Anthelmintic
drugs

11. Anthelmintics –
Drugs used in the treatment of infections with
helminths in the intestinal tract or tissues of the body
Examples :
• Mebendazole
• Albendazole
• Diethylcarbamazine
citrate (DEC)
• Ivermectin
• Praziquantel
• Pyrantel pamoate
• Piperazine
• Niclosamide

12. Mebendazole
Uses :
 Intestinal nematode infestation - roundworm,
hookworm, whipworm, pinworm & mixed worm
infestation
Adverse effects :
 GI side effects
 Skin rashes, itching, drug fever

13. Uses :
Intestinal nematode infestation - roundworm,
hookworm, whipworm, pinworm, threadworm &
mixed worm infestation
 Neurocysticercosis
 Hydatid disease
 Filariasis
Albendazole

14. Adverse effects :
 GI disturbances
 Headache, dizziness, fever & weakness
 Loss of hair
 Pancytopenia

15. Diethylcarbamazine citrate (DEC)
Uses :
 Filariasis
 Tropical eosinophilia
Adverse effects:
 Drug-induced effects – anorexia, nausea, vomiting,
headache & dizziness
 Parasite-induced effects – due to release of proteins from
dying parasites
Mazzotti reaction – fever, skin rashes, severe itching, chest
pain, muscle & joint pain, keratitis, lymphadenitis ,
eosinophilia & proteinuria

16. Anticancer
drugs

17. Examples
• Cyclophosphamide
• Cisplatin, carboplatin
• Methotrexate, 6-mercaptopurine
• 5-Fluorouracil
• Vinblastine, Vincristine
• Docetaxel, Paclitaxel
• Etoposide, Irinotecan
• Doxorubicin, Bleomycin
• Imatinib

18. Hormones and their antagonists:
Glucocorticoids - prednisolone
Estrogens - ethinyl estradiol
Antiestrogens - tamoxifen
Antiandrogens - flutamide
5α-reductase inhibitors - finasteride
GnRH analogues - nafarelin , abarelix
Progestins - hydroxyprogesterone-caproate

19. 1.Bone marrow suppression:
2. Immunosuppression
3. GIT :
Nausea and vomiting
Diarrhoea, stomatitis, GI bleeding & ulcers
• Leukopenia, agranulocytosis
• Thrombocytopenia, aplastic anemia
General toxicities

20. 4.Skin and hair : alopecia, dermatitis, rashes
5.Gonads
Oligozoospermia – males
Amenorrhea – females
6.Foetus
Abortion and fetal death
7. Hyperuricemia, gout
8. Carcinogenicity

21. Thank you