By Dr Eddy Bajrovic, Medical Director of Travelvax Australia.
Travel doctors get lots of questions from women about taking the contraceptive pill while travelling overseas. I’ll answer the most common ones.
How do I manage the change of time zones?
The contraceptive pill must be taken every 24 hours and it’s better to take it early rather than late. If the time difference means you would have to take your pill in the middle of the night, take it before you go to bed instead of in the morning. Some women take a second watch set to the time back home and stick to their normal pill-taking routine. But, that may not always be convenient if you’re travelling across a number of time zones. So, another option is to adjust to your destination’s time. Say, for instance, that your destination is 6 hours behind the time at home and that you normally take the pill at 7pm. Six days before you leave, start taking your pill an hour earlier each day. On your day of departure you’ll be taking the medication at 1pm. Once on board, adjust your watch forward to the destination time and the next time you take a pill it will be 7pm – you’re normal time back home. All you have to do is remember to take your pill as usual. Here’s a time zone converter to help you work out the time difference.
Will the pill still work if I become ill or get traveller’s diarrhoea?
Travellers' diarrhoea (TD) is the most common illness of travellers to developing countries, causing illness in up to 70% of those staying for two weeks or more. A bout of traveller's diarrhoea or vomiting could mean your body does not absorb the active medication in the pill. If you get sick during your travels use extra contraception during the period of illness and for the following 7 days. Your pill instruction leaflet will have more advice. Contraceptives that are delivered at a constant dose, such as by injection, by implant or by vaginal ring, are not affected by illness or time zone changes. They just need to be changed at the correct time.
What if I miss taking a pill?
Spotting, irregular periods, or even pregnancy may result if you are late or miss taking your contraceptive pill. (A ‘late’ pill is deemed to be less than 24 hours, while a ‘missed’ pill is when more than 24 hours has passed.)
If your pill is simply ‘late’ (less than 48 hours since the last dose) take the most recent missed pill as soon as you remember, and continue taking the remaining pills at your usual time. No additional protection is required.
However, if a pill is more than 24 hours late, take it as soon as you remember and keep taking pills at the usual time. However, you should also use other means of contraception until you have taken 7 active pills in a row.
Is deep vein thrombosis more of a risk if you are taking the pill?
Long-haul flights can increase the risk of deep-vein thrombosis (DVT), a condition that results in potentially fatal blood clots, usually in the legs. DVT is also a potential side-effect (albeit rare) of taking the contraceptive pill, which makes DVT a slightly higher risk for female travellers on long flights. (The same goes for car, bus or train journeys of over five hours.). DVT can also lead to the potentially fatal pulmonary embolism, when a piece of the clot breaks off and becomes lodged in the arteries to the lungs.
To avoid the potential for DVT, exercise your lower legs regularly while seated and take frequent walks in the cabin. (Try to secure an aisle seat so you can get up and move about the cabin more frequently.) You should avoid taking sleeping pills. Properly fitted graduated compression stockings will reduce the potential for DVT among those at higher risk, including women taking the pill.
High altitude travel can also raise the risk of DVT for women on the pill. Consider alternative contraception if you’re planning to stay at over 3500 metres for several weeks. The combined pill is definitely not recommended if you’ll be spending over a week at very high altitude (4500 metres or higher). Unexplained, severe pain in either calf muscle is a warning: Stop taking your contraceptive pills immediately and seek medical advice.
Aspirin has not been shown to be effective at preventing deep vein thrombosis. It is associated with an increased risk of gastrointestinal bleeding and shouldn’t be used to prevent the condition.
Do antibiotics affect the pill?
Studies have not clearly demonstrated any significant association between failures of the pill and the taking of antibiotics.
However, failures may occur in rare instances. This is particularly so if an antibiotic such as doxycycline, which is used as an anti-malarial, causes vomiting when taken around the same time as the pill and breakthrough bleeding occurs (an indication of inadequate hormone levels.)
Doxycycline can also cause thrush. If you occasionally suffer from the condition, tell your Travelvax doctor or GP if antimalarial medication is recommended for your trip.
If you’re prescribed any other drugs for travel or you buy some while travelling – especially antibacterial or anti-fungal medication – check your contraceptive pill’s instruction leaflet, or ask the doctor or a pharmacist about possible interactions.
What about emergency contraception?
If you missed taking your pill and were concerned about the risk of an unwanted pregnancy, the 'morning-after pill' is an option. While it should not be used as a regular form of contraception, it is useful to prevent pregnancy if a condom splits or if you have unprotected sex.
Most types consist of two pills – the first is taken within 72 hours of having unprotected sex, the second one 12 hours after the first. Unprotected sex can not only lead to an unwanted pregnancy: a sexually transmitted infection makes for a nasty holiday memento, too.
Take sufficient quantities of the pill and your regular drugs in their original packaging to cover your trip and any short delays.
Don’t forget medication for conditions that could recur, such as asthma. Even if you haven’t had an attack in some time, you may be exposed to a trigger during the journey and it’s better to be prepared with medication you know you can trust at hand.
(There are legal restrictions on the quantity of Pharmaceutical Benefits Scheme (PBS) drugs that a traveller can take or send overseas. Find out more from the Medicare Australia website.)
Carry several days’ medicine in your hand luggage in case checked bags are delayed or lost.
Like more healthy advice for your next overseas trip? Call Travelvax Australia’s travel health advisory service on 1300 360 164 (toll-free from landlines). We provide no-obligation, country-specific advice about vaccine-preventable diseases, as well as potential food-, water-, and insect-borne health risks.