Drug/Lab interactions-
Histrelin suppreses the pituitary -gonadal system. Results of diagnostic tests of pitutiary
 gonadrotropic and gonadal functions conducted after histrelin therapy may be affected.

Supprelin LA decreased mean serum insulin-growth factor- 1 levels by approximately
11% . Supprelein  LA  increased the serum concentration of dehydroepiandrosterone in
some cases. 

Advanced prostate cancer ( Vantas only  )

Most common adverse reactions-

Bruising, pain, soreness, erythema and swelling.

Local reactions after implant insertion-
Brusing 6%      pain.soreness/tenderness 2% 

Other less frequently reported-
Local infection - resolved after treatment with oral antibiotics
Inflammation - resolved without any treatment

CV -  hot flashes    60%

CNS -  fatigue 8%  headache  2%  insomnia 2%  libido decreased 2%

Dermatologic -  implant site reaction 4% 

GI - constipation 2%

GU  -  erectile dysfunction 2%  gynaecomastia 3%  renal function impairment 3%
          testicular atropy   4%

Hypersensitivity

Special precautions/warnings-

Supprelin LA - histralein like other GnRH agonists initially causes a transcient increase in
serum concentration of estradiol in females and testosterone in both sexes during the first
week of treatment, Patients may experience worsening symptoms or onset of new symtpoms
during this period.

Vantas - histrelin like other LH-RH   agonists causes a transcient increase in serum concentration of tstosterone during the first week of treatment. patients may experience worsening of symptoms or onset of new symptoms including bone pain, neuropathy, or uretral or bladder outlet obstruction. 

Implant insertion and removal - is a surgical procedure and it is important that instructions are followed  to avoid potential complications.
Insertion and removal of the implant should be done asceptically. Proper surgical procedure
 is important to minimise adverse reactions.

Pregnancy- posibilty exists that spontaneous abortion may occur.  Histralein is contraindicated in females who are or may become pregnant while receiving the drug.

Children- safety and efficacy in children younger than 2 years of age have not been established.  Use in children below 2 years of age is not recommended

Indications-
Advanced prostate cancer ( Vantas only  )

Dosage-
Recommended dosage-  is 1 implant every 3 months. The implant is inserted subcutaneously in the inner aspect of the upper arm  and provides continuous release of histrelin ( 65mcg/day. Supprelin LA and 50 to 60mcg/day for Vantas ) for 12 months of hormonal therapy

Histrelin implant must be removed after 2 months of therapy ( the implant has been designed to allow for flexibility of medical appointments. At the time as the implant is removed , another implant may  be inserted to continue therapy

Storage- refrigerate the small carton containg the small plastic pouch and glass vial
( with  the plastic pouch inside ) until the day of insertion.

Store the implant refrigerated 2 to 8C ( 36 to 46F ) in unopened  glass vial with sterile
sodium chloride 1.8% solution over wrapped in the amber plasstic pouch and carton.

Protect from light. Do not freeze

1. Advice patients that a transceint worsening of symptoms of puberty or onset of new symptoms may occur. initially with Supprelin LA . However within 4 weeks of of therapy complete   suppression of gonadal steroids occurs and manifestation of pubert decrease

2. Instruct patient from getting the inserted arm wet for 24 hours and strenous excertion
   of the inserted arm for 7 days after imlant indsertion to allow the incison to fully close.
   the adhesive elastic bandage can be removed at that time.

3. Instruct patients not  to remove the surgical strips, rather the strips should be allowed to
    fall off on their own after several days.

4. Advice patients to report to their doctor any severe pain,  redness, or swelling in
   and around implant site. Instruct patients to monitor the incion site ultil healed

5. Instruct patients to return for routine checks of their condition and to ensure the
  histelin implant is present and functioning in his/her body. 

Pregnancy-
Posibilty exists that spontaneous abortion may occur.  Histralein is contraindicated
in females who are or may become pregnant while receiving the drug.

Children-
Safety and efficacy in children younger than 2 years of age have not been established.
 Use in children below 2 years of age is not recommended