It is important that your doctor check your progress at regular visits to make sure that this medicine is working properly.
Check with your doctor before you stop taking this medicine. Your doctor may want you to reduce gradually the amount you are taking before stopping the medicine completely.
Make sure that you have enough medicine on hand to last through weekends, holidays, or vacations. You should not miss taking any doses. You may want to ask your doctor for another written prescription to carry in your wallet or purse. You can then have it filled if you run out of medicine when you are away from home.
Before having any kind of surgery (including dental surgery) or emergency treatment, make sure the medical doctor or dentist in charge knows that you are taking this medicine.
Do not take other medicines unless they have been discussed with your doctor. This especially includes over-the-counter (nonprescription) medicines for appetite control, asthma, colds, cough, hay fever, or sinus problems, since they may tend to increase your blood pressure.
This medicine will add to the effects of alcohol and other central nervous system (CNS) depressants (medicines that slow down the nervous system, possibly causing drowsiness). Some examples of CNS depressants are antihistamines or medicine for hay fever, other allergies, or colds; sedatives, tranquilizers, or sleeping medicine; prescription pain medicine or narcotics; barbiturates; medicine for seizures; muscle relaxants; or anesthetics, including some dental anesthetics. Check with your doctor before taking any of the above while you are using this medicine.
This medicine may cause some people to become drowsy or less alert than they are normally. This is more likely to happen when you begin to take it or when you increase the amount of medicine you are taking. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are not alert.
Dizziness, lightheadedness, or fainting may occur, especially when you get up from a lying or sitting position. Getting up slowly may help, but if the problem continues or gets worse, check with your doctor.
The dizziness, lightheadedness, or fainting is also more likely to occur if you drink alcohol, stand for long periods of time, exercise, or if the weather is hot. Drinking alcoholic beverages may also make the drowsiness worse. While you are taking this medicine, be careful to limit the amount of alcohol you drink. Also, use extra care during exercise or hot weather or if you must stand for long periods of time.
This medicine may cause a loss of potassium from your body.
- To help prevent this, your doctor may want you to:
- eat or drink foods that have a high potassium content (for example, orange or other citrus fruit juices), or
- take a potassium supplement, or
- take another medicine to help prevent the loss of the potassium in the first place.
- It is very important to follow these directions. Also, it is important not to change your diet on your own. This is more important if you are already on a special diet (as for diabetes), or if you are taking a potassium supplement or a medicine to reduce potassium loss. Extra potassium may not be necessary and, in some cases, too much potassium could be harmful.
Check with your doctor if you become sick and have severe or continuing vomiting or diarrhea. These problems may cause you to lose additional water and potassium.
For patients with diabetes:
- The chlorthalidone contained in this medicine may raise blood sugar levels. While you are using this medicine, be sure to test your blood sugar (glucose) level, or test for sugar in your urine.
This medicine may cause your skin to be more sensitive to sunlight than it is normally. Exposure to sunlight, even for brief periods of time, may cause a skin rash, itching, redness or other discoloration of the skin, or a severe sunburn. When you begin taking this medicine:
- Stay out of direct sunlight, especially between the hours of 10:00 a.m. and 3:00 p.m., if possible.
- Wear protective clothing, including a hat. Also, wear sunglasses.
- Apply a sun block product that has a skin protection factor (SPF) of at least 15. Some patients may require a product with a higher SPF number, especially if they have a fair complexion. If you have any questions about this, check with your health care professional.
- Apply a sun block for lips that has an SPF of at least 15 to protect your lips.
- Do not use a sunlamp or tanning bed or booth.
If you have a severe reaction from the sun, check with your doctor.
This medicine may cause dryness of the mouth. For temporary relief, use sugarless candy or gum, melt bits of ice in your mouth, or use a saliva substitute. However, if your mouth continues to feel dry for more than 2 weeks, check with your medical doctor or dentist. Continuing dryness of the mouth may increase the chance of dental disease, including tooth decay, gum disease, and fungus infections.