Co-Trimoxazole

What is Co-Trimoxazole for?

Co-trimoxazole is an antibiotic made up of two different antibiotics (sulfamethoxazole and trimethoprim). Sulfamethoxazole belongs to a group of medicines known as sulphonamides and trimethoprim belongs to a group of medicines known as benzylpirimidines.

It is used to prevent and treat infections caused by certain bacteria, fungi, and parasites. These may include infections of the lung, urinary tract, skin and soft tissue. Bactrim works by blocking two key steps in the growth of bacteria.

How should I take or use Co-Trimoxazole ?

Co-Trimoxazole may come in the form of a tablet, syrup, or an injection, which will be chosen by your physician. This medication may be taken with or without food.

You should complete each course of antibiotics as prescribed even if you feel better. Incomplete treatment might cause the infection to return or lead to antibiotic resistance. When antibiotic resistance happens, the antibiotic will not be effective anymore.

What should I do if I forget to take or use Co-Trimoxazole ?

If you forget to take a dose, take it as soon as you remember. However,  if it is almost time for your next dose, skip the missed dose and take the next dose at the usual scheduled time. Do not take two doses to make up for the missed dose.

What precautions should I take when taking or using Co-Trimoxazole ?

Inform your healthcare professional if:

• You are allergic to sulfamethoxazole, trimethoprim, Co-trimoxazole or any of this medication.
• You are allergic to sulfa drugs (such as gliclazide or glibenclamide used for diabetes or thiazide diuretics used for high blood pressure) or have ever developed any rash, hives, swelling or shortness of breath after taking a sulfa drug.
• You have a blood disorder that causes bruises or bleeding (thrombocytopenia), folate vitamin deficiency that causes you to feel tired, weak and breathless (anaemia) or a rare blood disorder called porphyria which can affect the skin or nervous system.
• You have a certain disorder known as glucose-6-phosphate dehydrogenase (G6PD) deficiency.
• You have asthma, kidney or liver disease.
• You are pregnant, planning to become pregnant, or breastfeeding.
• You are taking any other medications, including supplements, traditional medications and herbal remedies. These include:
  • Blood thinners such as warfarin
  • Methotrexate, a medicine used to treat certain cancers or certain diseases affecting the immune system
  • Phenytoin, a drug used to treat epilepsy (fits)
  • Drugs that can increase potassium levels such as ACE inhibitors (e.g. captopril, lisinopril), angiotensin receptor blockers (e.g. losartan) or aldosterone antagonists (e.g. spironolactone)
  • Medicines that are used to treat diabetes, such as glipizide or glibenclamide
  • Medicines used to treat problems with your arrhythmia (problem with your heartbeat) such as procainamide
  • Folinic acid

What are some common side effects of Co-Trimoxazole ?

• The most common side effects are gastrointestinal disturbances (nausea, vomiting, diarrhea, loss of appetite).
  • Take co-trimoxazole with a meal or a snack to reduce these side effects. If symptoms are severe or do not go away, consult your doctor.
• This medication may make your skin more sensitive to the sun, hence you may get sunburn more easily.
  • Apply sunblock, wear long sleeved clothing, and avoid prolonged direct sunlight to protect yourself from the sun.
• This medication may cause a fungal infection called thrush or candidiasis if taken for a long period of time.
  • Contact your doctor if you experience vaginal itching and/or discharge or notice white spots in the lips/mouth.

What are some rare but serious side effects that I need to seek medical advice immediately?

Stop taking co-trimoxazole and tell your doctor immediately if you have an allergic reaction. The symptoms of a drug allergy include one or more of the following:

• Swollen face/eyes/lips/tongue
• Difficulty in breathing
• Skin rashes over your whole body

In rare instances, the skin rash may be followed by a more severe reaction, such as Stevens-Johnson Syndrome (SJS) and toxic epidermal necrolysis (TEN). These are life-threatening skin reactions, that are characterized by skin rash, multiple ulcers in the mouth/throat/nose/genitals, fever, and may progress to widespread blistering or peeling of the skin. Hence, do seek urgent advice from a healthcare provider immediately if any of the above occur.

Other rare side effects include:

• Blood disorders – Signs of reduced:
  • Red blood cells - which can make the skin pale and cause weakness or breathlessness (anaemia) – Monitor for signs of extreme tiredness
  • Platelets (that help to stop bleeding) – Monitor for signs of abnormal bleeding or bruising
  • White blood cells (that help defend against infections) – Monitor for signs of infection such as prolonged fever or sore throat
• Liver damage
  • Yellowing of your skin and whites of the eyes
  • Dark coloured urine or light-coloured stools
  • Nausea and vomiting that does not go away
  • Loss of appetite
  • Stomach pain
• Kidney problems
  • Monitor for swelling or puffiness in the face, abdomen, thighs or ankles or problems with urination
• Changes in electrolyte levels in the blood – High levels of potassium (which can cause abnormal heart beats) or low levels of sodium
  • Blood tests to monitor these electrolytes are usually carried out by your physician
• Severe intestinal condition (Clostridium difficile-associated diarrhoea) due to resistant bacteria. This may occur while receiving therapy or even weeks after treatment has stopped.
  • Inform your doctor immediately if you develop: persistent diarrhoea, stomach pain/cramping or mucus in your stool

If you experience any of these symptoms, you should stop your medications and see your healthcare professional immediately.

How should I store Co-Trimoxazole ?

Keep this medicine away from heat and direct sunlight in a cool, dry place, out of reach of children

How do I throw away Co-Trimoxazole safely?

Pack the medication into a bag and bring it back to the pharmacy where you received the medication from.