General
Clinical benefit from PANHEMATIN depends on prompt administration. Attacks
of porphyria may progress to a point where irreversible neuronal damage has
occurred. PANHEMATIN therapy is intended to prevent an attack from reaching
the critical stage of neuronal degeneration. PANHEMATIN is not effective in
repairing neuronal damage.9
Recommended dosage guidelines should be strictly followed. Reversible renal
shutdown has been observed in a case where an excessive hematin dose (12.2 mg/kg)
was administered in a single infusion. Oliguria and increased nitrogen retention
occurred although the patient remained asymptomatic.4 No worsening
of renal function has been seen with administration of recommended dosages of
hematin.9
A large arm vein or a central venous catheter should be utilized for the administration
of PANHEMATIN to avoid the possibility of phlebitis.
Since reconstituted PANHEMATIN is not transparent, any undissolved particulate
matter is difficult to see when inspected visually. Therefore, terminal filtration
through a sterile 0.45 micron or smaller filter is recommended.
Tests for Diagnosis and Monitoring of Therapy
Before PANHEMATIN therapy is begun, the presence of acute porphyria must be
diagnosed using the following criteria:9
- Presence of clinical symptoms.
- Positive Watson-Schwartz or Hoesch test. (A negative Watson-Schwartz or
Hoesch test indicates a porphyric attack is highly unlikely. When in doubt
quantitative measures of δ -aminolevulinic acid and porphobilinogen
in serum or urine may aid in diagnosis.)
Urinary concentrations of the following compounds may be monitored during
PANHEMATIN therapy. Drug effect will be demonstrated by a decrease in one or
more of the following compounds.3-6
ALA – δ -aminolevulinic acid
UPG – uroporphyrinogen
PBG – porphobilinogen
corproporphyrin
Carcinogenesis, Mutagenesis, Impairment of Fertility
No data are available on potential for carcinogenicity, mutagenicity or impairment
of fertility in animals or humans.
Pregnancy
Teratogenic effects-Pregnancy Category C: Animal reproduction studies
have not been conducted with hematin. It is also not known whether hematin can
cause fetal harm when administered to a pregnant woman or can affect reproduction
capacity. For this reason PANHEMATIN should not be given to a pregnant woman
unless the expected benefits are sufficiently important to the health and welfare
of the patient to outweigh the unknown hazard to the fetus.
Nursing Mothers
It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when PANHEMATIN is administered to a nursing woman.
Pediatric Use
Safety and effectiveness in pediatric patients under 16 years of age have not been established.
Geriatric Use
Clinical studies in PANHEMATIN did not include sufficient numbers of subjects
aged 65 and over to determine whether they respond differently from younger
subjects. Other reported clinical experience has not identified differences
in response between the elderly and younger patients. In general, dose selection
for an elderly patient should be cautious, usually starting at the low end of
the dosing range, reflecting the greater frequency of decreased hepatic, renal,
or cardiac function, and of concomitant disease or other drug therapy.
REFERENCES
3. Lamon, J. M., Hematin Therapy for Acute Porphyria, Medicine
58(3):252-269, 1979.
4. Dhar, G. J., et al., Effects of Hematin in Hepatic Porphyria,
Ann Intern Med 83:20-30, 1975.
5. Watson, C. J., et al., Use of Hematin in the Acute Attack
of the "Inducible" Hepatic Porphyrias, Adv Intern Med 23:265-286,
1978.
6. McColl, K. E., et al., Treatment with Haematin in Acute Hepatic
Porphyria, Q J Med, New Series L (198):161-174, Spring, 1981.
9. Pierach, C. A., Hematin Therapy for the Porphyric Attack,
Semin Liver Dis 2(2):125-131, May, 1982.
Last updated on RxList: 11/7/2008