For instance, gelatine capsules at high temperature may soften, ointments and creams may become runny or watery, and suppositories may melt.
Medicines taken for acute conditions should not be greatly affected by a few days at temperatures higher than normal, but if you are in an area of regular and prolonged high temperatures your medicines should be stored in the coolest, safest place available.
Moisture and medicines don’t go hand in hand. They deteriorate quickly when exposed to extremely high humid conditions. Therefore, Medicines should not be kept in the bathroom or places, where heat and humidity are common and can affect them. Always check the label and the Consumer Medicine Information (CMI) leaflet for storage instructions and talk to your pharmacist if you have any questions.
In general, it is vital to try and store medicines away from heat, moisture and sunlight. There are many medicines which are light sensitive, and they are destroyed when exposed to sunlight. Such medicines should be placed in dark and closed containers. Most medicines should be stored below 25°C and they should never be left in warm places such as in front of a window where the temperature can reach high levels.
NPS MedicineWise advises that people living in the tropics should store their medicines in a part of the house that is cool and dry, for example in an airtight container in the linen cupboard. They should be checked regularly to see that they remain dry, especially during the wet season.
An exception to never storing medicines in the fridge is some liquid medicines and injection vials but only if the label says so. The fridge means the main compartment, not the freezer and if your medicines accidentally freeze, they are almost certainly unstable and therefore should not be used. Once again, consult with your pharmacist.
For patients with such chronic illnesses as diabetes or heart disease, damaged or deteriorated medicine can result in serious consequences, so it is not worth taking a risk.