Drug Interaction:
Drug interactions -summary-
Indinavir-
rifapentine should be used with extreme caution if at all, in patients who are taking
protease inhibitors
Cytochrome P450-
rifapentene is an inducer of cytochromes P450 3A4 P450 2C8/9. Rifapentene may increase
the metabolism of other coadministred drugs that are metabolised by these enzymes.
Indication:
Pulmonary tuberculosis
Adverse Reaction:
Adverse reactions-
Dermatologic - urticaria, skin discoloration,
GI - constipation, esophagitis, gastritis, pancreatitis
Hematologic - thrombocytopenia, neutropenia, leukocytosis, purpura, hematoma
Hepatic- bilirubinemia, hepatitis
Metabolic- /nutritional - hyperkalemia, hypervolemia, alkaline phosphatase increased,
LDH increased
Musculoskeletal - gout, arthiritis
Miscellaneous- aggressive reaction, peripheral edema, fatigue
Contra-Indications:
Hypersensitivity
Special Precautions-
Compliance - compliance with full course of therapy must be emphasised and the importance of
not missing must be stressed
Psuedomonous colitis- if pseudomonous colitis is suspected rifapentine should be stopped
immediately and patient should be treated with supportive and specific treatment without
delay
Red discoloration body fluids- rifapentine may produce a predominantly red-orange dscoloration
of body tissues and fluidseg skin, teeth, tongue, feces, urine, sputum, sweat, cerebrospinal fluid
Contact lens and dentures may become permanently stained
Porphryia- rifapentine should not be used in patients with porphyria
Hepatic function impairment - patients with abnormal hepatic function should be given refapentine
only under medical supervision. Necessary caution should be excercised
Pregnancy- rifapentine should be used during pregnancy only if needed.
Lactation- since rifapentine may produce a orange red discoloration of body fluids, there is
a potential for discoloration of breast milk.
Children- safety and effctiveness of riapentine not established
Elderly- elderly patients should be cautious, usually starting with a low dose and monitor
progress during therapy
Dosages/ Overdosage Etc:
Indication-
Pulmonary tuberculosis
Dosage-
Intentive short trem therapy- which is continue for 2 months, 600mg ( four 150mg tablets ) of
rifapentine oral should be given twice weekly with an interval of not less than 3 days (72hours )
between doses.
For those patients with propensity for vomting or gastro-intestinal upset , administration
with food will be useful.
Patient Information:
1. Take with food if vomiting or GI upset occurs
2,.Patients should be told that rifapentine Red discoloration body of body tissues and fluids
eg.skin, teeth, tongue, feces, urine, sputum, sweat, cerebrospinal fluid
Contact lens and dentures may become permanently stained
3.patients hould be instructed to notify their physician if they experience , fever, loss of
appetite, malaise, nausea, vomiting, darkened urine, yellowish discolroation of skin
and eyes and pain or swelling of the joints.
4. Compliance of full course of therapy must be emphasised and the importance of not
missing any doses of the daily administered in the intensive phase must be stressed.
Pharmacology/ Pharmacokinetics:
Ref - Drug Facts And comparisons(2010)
Pharmacology-
Rifapentine is cyclopentyl rifamycin, inhibits DNA dependent RNA polymerase in
suspension strains of Myobacterium tuberculosis but not in mammalian cells.At
therapeutic levels rifapentine exhibits bacterial activity against both intercellular
and extracellular M tuberculosis organisms.
Pharmacokinetics-
The absolute bioavailability of rifapentine has not been determined (with oral
solution as a reference) of rifapentine after a single 600mg dose of healthy
adult volunteers was 70%. Maximum concentrations were acheived from 5 to 6 hours
after administration of the 600mg rifapentine dose.
Select Pharmacokinetic Parameters of Rifapentine
Parameter Rifapentine 25-desacetyl
(n=12) rifapentine
(n=12)
Cmax (mg/mL) ~15.05 ~6.26
AUC (0-72h) (mcg*h/mL) ~319.54 ~215.88
t 1/2 (h) ~13.19 ~13.35
Tmax (h) ~4.83 ~11.25
Cl (L/hr) ~2.03 -
Interaction with Food:
Take with food if vomiting or GI upset occurs
Pregnancy and lactation:
Pregnancy-
Rifapentine should be used during pregnancy only if needed.
Lactation-
Since rifapentine may produce a orange red discoloration of body fluids, there is
a potential for discoloration of breast milk.
Children-
Safety and effctiveness of riapentine not established
Elderly-
Elderly patients should be cautious, usually starting with a low dose and monitor
progress during therapy
Manufacturer Details