Workshop: Hormonal Contraception (further practice)
1
Case Scenario 7
Question
What further
background
information do
you need to
clarify the
question and
minimise the risks
when advising the
caller?
Is it okay to take Vibramycin whilst taking the pill? I forgot to check that the
doctor knew I was taking the pill.
PERSON
MEDICINES
Who is asking?
28 year old female - about herself
Medicines?
Vibramycin 200mg today then
100mg a day. 10-day course.
New or worsening symptoms?
GP diagnosed a chest infection this Loestrin 20.
morning.
Have you taken the antibiotic?
No.
Allergies?
None known.
Medical conditions?
None.
How many pills left?
14 pills.
Gather the further background information BEFORE searching for information.
What information
sources would
you use?
eBNF:
Loestrin 20 : Low strength COC. 21 day packet.
Vibramycin: doxycycline (as hyclate) 50 mg
Some broad-spectrum antibiotics (e.g.ampicillin, doxycycline) may reduce
the efficacy of combined oral contraceptives by impairing the bacterial flora
responsible for recycling of ethinylestradiol from the large bowel. FPA
advice is that additional contraceptive precautions should be taken whilst
taking a short course of a broad-spectrum antibiotic and for 7 days after
stopping. If these 7 days run beyond the end of a packet the next packet
should be started immediately without a break (in the case of ED tablets the
inactive ones should be omitted). If the antibiotic course exceeds 3 weeks,
the bacterial flora develops antibiotic resistance and additional precautions
become unnecessary; additional precautions are also unnecessary if a
woman starting a combined oral contraceptive has been on a course of
antibiotics for 3 weeks or more.
eMC / Loestrin 20 :
The effectiveness of combined oral contraceptives may be considerably
reduced by interaction with drugs that induce hepatic enzyme activity e.g.
carbamazepine, griseofulvin, phenytoin, phenobarbital, primidone and
rifampicin. Other drugs suspected of having the capacity to reduce the
efficacy of oral contraceptives include ampicillin and other broad-spectrum
antibiotics.
netdoctor / Loestrin 20 :
However, if you are prescribed another antibiotic medicine (eg amoxicillin,
doxycycline) while taking this contraceptive, there is a very low risk that the
antibiotic may make your pill less effective at preventing pregnancy.
Although the risk of this is very low, the personal and ethical consequences
of an unwanted pregnancy can be very serious. For this reason, it is
recommended that you use an extra method of contraception (eg condoms)
while you are taking the antibiotic and for seven days after finishing the
course. If these seven days run beyond the end of a pill packet, a new
NA & HIA Role Preparation: Hormonal Contraception & EHC
Updated November 2007
Workshop: Hormonal Contraception (further practice)
packet should be started without a break. For more information talk to your
pharmacist.
FPA:
Common antibiotics – continue taking your pill as usual and use an extra
method of contraception while taking the antibiotics anf for 7 days
afterwards. If you get to the end of your packet or end of the active pills in
Every Day pills while you are still taking the antibiotic or using extra
precautions then start a new packet straight away. Do not have your usual
7-day break or take your placebo tablets. You may or may not bleed this is
normal. You are protected against pregnancy.
Stockley’s Drug Interactions:
The oral contraceptive/tetracycline interactions summarised here are all that
have been identified in the world’s literature involving the drugs cited. Much
of the evidence is anecdotal with insufficient controls (if any). These
interactions are not adequately established and the whole issue remains
controversial. Bearing in mind the extremely wide use of both drugs, any
increase in the incidence of contraceptive failure above the accepted failure
rate is clearly very low indeed. On the other hand, the personal and ethical
consequences of an unwanted pregnancy can be very serious. For this
reason, some authorities recommend that, for maximal protection, a second
form of contraception (a barrier method) should be used routinely while
taking a short course of tetracyclines, and for 7 days afterwards. In addition,
the UK Family Planning Association (FPA) recommends that, when using a
tetracycline, if the 7 days run beyond the end of a packet, the new packet
should be started without a break, omitting any of the inactive tablets. While
accepting the sense of this advice, others contend that these instructions
may confuse patients, and complicate pill taking, and could have the
opposite effect of increasing the user-failure rate of oral contraceptives.
What advice
would you give?
Or would you
refer?
There is a risk that doxycycline may stop the pill from working properly.
Use a barrier method or abstinence during the time that you are on the
antibiotic and for 7 days following the end of the course (i.e. 14 days).
Also, start the next pack of pills straight away without the 7-day pill free
period. You will not get the usual withdrawal bleed.
NA & HIA Role Preparation: Hormonal Contraception & EHC
Updated November 2007
Workshop: Hormonal Contraception (further practice)
Case Scenario 8
Question
Further
background
information
A woman telephones to say she is going into hospital to have an operation
and wants to know if she can carry on with her pill as usual during that time.
Which pill does she take?
Minulet
What surgery is she going to have?
An operation to fix her varicose veins.
When is she going into hospital?
6 weeks time.
Gather the further background information BEFORE searching for information.
What information
sources would
you use?
eBNF:
Minulet: COC
Surgery: Oestrogen-containing contraceptives should preferably be
discontinued (and adequate alternative contraceptive arrangements made)
4 weeks before major elective surgery and all surgery to the legs or surgery
which involves prolonged immobilisation of a lower limb; they should
normally be recommenced at the first menses occurring at least 2 weeks
after full mobilisation.
NetDoctor:
The risk of blood clots forming in the veins (venous thromboembolism) while
taking the pill may be temporarily increased if you are immobile for
prolonged periods of time, for example if you have a major accident or major
surgery. For this reason, your doctor will usually recommend that you stop
taking this pill for a period of time (usually four to six weeks) prior to any
planned surgery, particularly abdominal surgery or orthopaedic surgery on
the lower limbs (but not before minor surgery like teeth extraction). You will
also need to stop taking this pill if you are going to be immobile for long
periods, for example because you are confined to bed or have a leg in a
plaster cast. You should not start taking the pill again until at least two
weeks after you are fully mobile.
eMC:
No advice.
FPA:
No advice.
What advice
would you give?
Or would you
refer?
The operation is on your legs so you must stop taking your pill 4 weeks
before you go into hospital and you must not start it again until your first
period which happens at least 2 weeks after you are fully up and about.
You should use other contraceptive protection during this time.
Give her sources of further advice e.g. Family planning clinic, GP, FPA.
NA & HIA Role Preparation: Hormonal Contraception & EHC
Updated November 2007
Workshop: Hormonal Contraception (further practice)
Case Scenario 9
Question
What further
background
information
A woman telephones to say she is going on holiday next week. She read in
a magazine that the risk of blood clots during a flight is worse in someone
who takes the pill. Can you advise her?
What pill does she take?
Trinordiol
Where is she going on holiday?
DisneyLand – California
Gather the further background information BEFORE searching for information.
What information
sources would
you use?
eBNF:
Trinordiol – triphasic COC.
6 light brown tablets, ethinylestradiol 30 mcg, levonorgestrel 50 mcg
5 white tablets, ethinylestradiol 40 mcg, levonorgestrel 75 mcg;
10 ochre tablets, ethinylestradiol 30 mcg, levonorgestrel 125 mcg
eBNF:
Travel
Women taking oral contraceptives may be at an increased risk of deep-vein
thrombosis during travel involving long periods of immobility (over 5 hours).
The risk may be reduced by appropriate exercise during the journey and
possibly by wearing elastic hosiery.
NetDoctor:
There may also be an increased risk of blood clots in the veins if you are
travelling for long periods of time where you will be sat still (over five hours).
The risk of blood clots during long journeys may be reduced by appropriate
exercise during the journey and possibly by wearing elastic hosiery. Discuss
this with your doctor
eMC/SPC Trinordiol: last revision of text : 3 March 2003:
No further useful information.
eMC PIL Trinordial: update: 3 March 2003:
No further useful information.
FPA:
No specific advice concerning travel.
What advice
would you give?
Or would you
refer?
As you take the contraceptive pill and are going on a flight longer than 5
hours there may be an increased risk of blood clots in the leg.
During the flights you should move around as much as possible and maybe
do some leg exercises too.
Wear ‘flight socks’ during the journeys. You can buy ‘flight socks’ and get
advice on the correct sizing from your community pharmacist.
NA & HIA Role Preparation: Hormonal Contraception & EHC
Updated November 2007
Workshop: Hormonal Contraception (further practice)
NA & HIA Role Preparation: Hormonal Contraception & EHC
Updated November 2007
Workshop: Hormonal Contraception (further practice)
Case Scenario 10
Question
Further
background
information
A 38-year old lady would like to know more information about why the
pharmacist would not sell her Levonelle One Step. She was told to see her
GP or Family Planning Clinic as soon as possible.
PERSON
MEDICINES
Who is asking?
38-year old female.
Medicines (name, dose, freq)?
Asacol® 400mg tds.
New or worsening symptoms?
No symptoms.
Unprotected intercourse?
Yes, 24 hours ago.
Any allergies/medical conditions? Where in menstrual cycle?
Crohn’s disease for the last 4 years. Day 7.
Last relapse about 2 months ago.
Gather the further background information BEFORE searching for information.
What information
sources would
you use?
eBNF: Asacol®: Mesalazine 400mg MR tablets.
Interactions: None stated with mesalazine
Cautions: see notes above; past ectopic pregnancy, severe malabsorption
syndromes, severe liver disease (Appendix 2), pregnancy (see notes above
and Appendix 4); breast-feeding (Appendix 5); interactions: see notes above
and Appendix 1 (progestogens)
eMC:
Severe malabsorption syndromes, such as Crohn's disease, might impair
the efficacy of Levonelle One Step. Women suffering from these conditions
should be referred to a doctor for emergency contraception.
No interaction stated with mesalazine.
NetDoctor:
Use with caution in Crohn's disease.
FPA:
No information about Crohn’s disease.
What advice
would you give?
The manufacturer of Levonelle warns that severe malabsorption syndromes,
such as Crohn's disease, might impair the absorption and efficacy of
Levonelle One Step. Women suffering from these conditions should be
referred to a doctor for emergency contraception.
Your doctor will assess how severe your Crohn's disease is and whether it is
likely to reduce the absorption and efficacy of Levonelle 2.
You should see your doctor or go to a Family Planning Clinic immediately as
the longer you delay emergency contraception, the less effective it will be.
NA & HIA Role Preparation: Hormonal Contraception & EHC
Updated November 2007
Workshop: Hormonal Contraception (further practice)
Case Scenario 11
Question
Further
background
information
Caller is asking whether Hypericum will stop the morning after pill working.
Heard that taking SJW can stop the Morning After Pill working. She does
not want to use a regular hormonal contraceptive and generally relies on
barrier methods – but accidents can and occasionally do happen.
PERSON
MEDICINES
Who is asking?
38-year old female.
Name, dose, freq?
Hypericum perforatum 300mg three
times a day.
Any allergies/medical conditions?
Self diagnosed / treated depression.
Unprotected intercourse?
No.
Gather the further background information BEFORE searching for information.
What information
sources would
you use?
eBNF :
St John’s wort (Hypericum perforatum) is a popular unlicensed herbal
remedy for treating mild depression. However, preparations of St John’s
wort can induce drug metabolising enzymes and a number of important
interactions with conventional drugs have been identified, see Appendix 1
(St John’s wort) The amount of active ingredient can vary between different
preparations of St John’s wort and switching from one to another can
change the degree of enzyme induction.
Appendix 1: SJW interactions with progestogens: St John's wort reduces
contraceptive effect of progestogens (avoid concomitant use).
eMC / SPC Levonelle One Step Last revision of text 14 June 2004:
Interactions: The metabolism of levonorgestrel is enhanced by concomitant
use of liver enzyme inducers. Drugs suspected of having the capacity to
reduce the efficacy of levonorgestrel containing medication include…herbal
medicines containing Hypericum perforatum (St. John's Wort). Women
taking such drugs should be referred to their doctor for advice.
NetDoctor:
St John’s wort – a natural remedy for depression? A simple but useful
discussion re the benefits and risks of SJW from two points of view, but no
relevant information for this enquiry.
Critical thinking
The information insufficient to gauge the likelihood of EHC failure or if
options other than stopping the SJW are available. Consider referral to
UKMi, and/or the caller sees her doctor or Family Planning Clinic. Doubling
the dose of the Levonelle may be effective but this is unlicensed use and a
doctor must take responsibility for prescribing it – Pharmacists cannot
normally supply Levonelle in this situation.
What advice
would you give?
It appears that taking Hypericum perforatum or St John’s Wort may reduce
the effect of the EHC (Levonelle) possibly causing it to fail. For more
information about this, I can refer you to a specialist pharmacist. You may
also like to consider speaking to your GP or FP clinic.
NA & HIA Role Preparation: Hormonal Contraception & EHC
Updated November 2007
Workshop: Hormonal Contraception (further practice)
Case Scenario 12
Question
Further
background
information
A schoolteacher telephones. She has been given a 2-day course of
rifampicin as one of her pupils had been hospitalised with meningitis. She
uses Evra patches and wants to know whether the rifampicin will affect it.
PERSON
Who is asking?
34-year old female.
Any allergies/medical conditions?
None.
MEDICINES
Name, dose, freq?
Rifampicin 600mg every 12 hours for
2 days. Not started yet.
Evra - patch week 2
Did she tell the Dr on Wevra?
No, forgot.
Gather the further background information BEFORE searching for information.
What information
sources would
you use?
eBNF:
Evra: combined hormonal patches (releasing ethinylestradiol approx.
20 micrograms/24hrs and norelgestromin approx. 150 micrograms/24 hr);
The effectiveness of contraceptive patches can also be reduced by drugs that
induce hepatic enzyme activity. Additional contraceptive precautions are
required whilst taking the enzyme-inducing drug and for 4 weeks after stopping.
Rifampicin: are such potent enzyme-inducing drugs that an alternative method
of contraception… is always recommended. Since enzyme activity does not
return to normal for several weeks after stopping an enzyme-inducing drug,
appropriate contraceptive measures are required for 4 to 8 weeks after
stopping.
NetDoctor:
If you are prescribed the antibiotics rifampicin or rifabutin, an alternative
method of contraception is usually always recommended, because these
particular antibiotics make hormonal contraceptives so ineffective.
eMC / SPC Evra last revision of text January 2007
Medicinal product interactions, which result in an increased clearance of sex
hormones can lead to … hormonal contraceptive failure. This has been
established with…rifampicin. The mechanism of these interactions appears to
be based on the hepatic enzyme inducing properties of these medicinal
products. Maximal enzyme induction … may be sustained for at least 4 weeks
after cessation of therapy.
Women on treatment with any of these medicinal products should temporarily
use a barrier method in addition to EVRA or choose another method of
contraception. With microsomal enzyme-inducing drugs, the barrier method
should be used during the time of concomitant administration of these
medicinal products and for 28 days after their discontinuation. Women on
treatment with antibiotics (except tetracycline) should use the barrier method
until 7 days after discontinuation.
eMC / SPC Rifadin Capsules last revision of text March 2006:
Patients are advised to use alternative, non-hormonal methods.
FPA:
Some advice but does not specifically state rifampicin, just medicines for TB.
NA & HIA Role Preparation: Hormonal Contraception & EHC
Updated November 2007
Workshop: Hormonal Contraception (further practice)
Critical thinking:
Consider referral back to doctor for an alternative prophylactic antibiotic.
What advice
would you give?
The effectiveness of Evra is considerably reduced by rifampicin and for a
long-time after she finishes it.
She should use another method of contraception while taking the rifampicin
and for at least 4 weeks after stopping it.
She could continue to use the Evra as normal during this time but it won’t
be fully effective.
She may also consider going back to the doctor as there may be an
alternative antibiotic she can take.
NA & HIA Role Preparation: Hormonal Contraception & EHC
Updated November 2007