Drug interactions -summary

Quinine sulphate +

Aluminium contng antacids-
    delay or decrease absorption of concurrent quinine.
 
Anticoagulants oral -
   quinine  depress the hepatic enzyme system that synthesis
      Vitamin K  dependent clotting factors and enhance the action of
      warfarin and other oral anticoagulants

Cimetidine
    reduce quinine oral clearance and increase its elimination half-life.

Digoxin
    serum concentrations  increased by concurrent quinine.

Mefloquine
   do not use concurrently with quinine.
    if required to be used delay meloquine admin. by at least 12 hours
     after last dose of quinine. Risk of convulsions increased by coadmin.
 
Neuromuscular  blocking agents-
    blockade of these agents is potentiated by quinine, and  result
     in respiratory difficulties

Urinary   alkalinizers , acetazolamide ,  Sod bicarb
     administered concurrently with quinine  increase quinine blood levels.

Drug/Lab Test Interaction: Elevated values for 17 ketogenic steroids may occur with Zimmerman method.

Malaria 

Cichonism may occur in therapeutic doses. Acute hemolysis, hemolytic anemia,

Thrombocytopenic purpura Agranulocytosis, hyperprothrombinemia.

Visual disturbances, including disturbed colour vision and perception,

Photophobia,blurred vision with scotomata Night blindness, amyblyopia,

Diplopia,diminished visual fields. Tinnitus, deafness, Vertigo, headache, fever,

Apprehension, reslessness, Confusion, syncope.

Cutaneous rashes, flushing, Sweating, facial oedema.

Hypersensitivity to quinine,glucose -6-phosphate dehydrogenase(G6PD) deficiency, optic neuritis, history of back water fever and thrombocytopenic purpura (associated with previous quinine ingestion), pregnancy.

Special precautions:

Discontinue quinine if there is any evidence of hypersensitivity. Continuous flushing, pruritus, skin rashes, fever, gastric distress, dyspnea, ringing in the ears and visual impairment may occur, particularly only with small doses of quinine.

Extreme flushing of the skin followed by intense,generalised pruritus is most common.

Pregnancy- Quinine has an oxytocic action that appears to occur only with doses that are higher than those recommended It also crosses the placenta. Congenital malformation have occured primarily in large doses (upto 30g) for attempted abortion.

Lactation- Quinine is excreted in breast milk in small amounts. Although no adverse efects have been reported in the nursing infant, rule out patients at risk for G6PD deficiency before breast feeding.

Indication

Malaria

Dosage:

Adults- 650mg every 8 hours for 5 to 7 days

Children- 25mg/kg/day in divided doses every 8 hours for 5 to 7 days..

Vestibular Disorders

Drugs causing adverse reactions ( 388 )

1. Aminoglycosides

2. Quinine

3. Mustine

1.To be taken with meals or after meals.

2. May cause diarrhea, nausea, stomach cramps, or pain and vomiting, ringing of ear. Notify physician

3. Stop the drug if there is an indication of allergy, viz flushing, itching, rash.

. AVOID CONCURRENT USE WITH ERYTHROMYCIN

Not significant

Pregnancy-

Quinine has an oxytocic action that appears to occur only with doses that are higher than those recommended It also crosses the placenta. Congenital malformation have occured primarily in large doses (upto 30g) for attempted abortion.

Lactation

Quinine is excreted in breast milk in small amounts. Although no adverse efects have been reported in the nursing infant, rule out patients at risk for G6PD deficiency before breast feeding.