Generic Name: guanethidine and hydrochlorothiazide (gwhan ETH i deen and hye droe klor oh THYE a zide)Brand Names: Esimil
Guanethidine lowers blood pressure by decreasing the levels of certain chemicals in your blood. This allows your blood vessels (veins and arteries) to relax and your heart to beat more slowly and easily.
Hydrochlorothiazide is a thiazide diuretic (water pill). It helps to lower your blood pressure and decrease edema (swelling) by increasing the amount of salt and water you lose in your urine.
Guanethidine and hydrochlorothiazide is used to treat high blood pressure.
Guanethidine and hydrochlorothiazide may also be used for purposes other than those listed in this medication guide.What is the most important information I should know about guanethidine and hydrochlorothiazide?Stand up slowly from a sitting or lying position. Guanethidine and hydrochlorothiazide may make you feel dizzy. Do not stop taking guanethidine and hydrochlorothiazide suddenly. Even if you feel better, you need this medication to control your condition. Stopping suddenly could cause severe high blood pressure, anxiety, and other dangerous side effects.
Tell your doctor and dentist that you are taking this medication before having surgery.
You must not take guanethidine and hydrochlorothiazide if you
have congestive heart failure; or
are taking a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), phenelzine (Nardil), or tranylcypromine (Parnate).
Before taking this medication, tell your doctor if you have
peptic ulcer disease (stomach ulcers) or other stomach problems,
a collagen vascular disease such as systemic lupus erythematosus,
high levels of cholesterol or triglyceride (types of fat) in your blood,
any type of heart disease.
You may require a lower dose or special monitoring during therapy with guanethidine and hydrochlorothiazide if you have any of these conditions.Guanethidine and hydrochlorothiazide is in the FDA pregnancy category B. This means that it is not expected to harm an unborn baby. Do not take this medication without first talking to your doctor if you are pregnant. Guanethidine and hydrochlorothiazide passes into breast milk and may harm a nursing infant. Do not take this medication without first talking to your doctor if you are breast-feeding a baby. Guanethidine and hydrochlorothiazide has not been approved for use by children.
Take guanethidine and hydrochlorothiazide exactly as directed. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you.Take each dose with a full glass of water. Take guanethidine and hydrochlorothiazide with food or milk if it upsets your stomach.
Do not stop taking guanethidine and hydrochlorothiazide. Stopping suddenly could make your condition much worse or cause very serious side effects.Store this medication at room temperature away from moisture and heat.
See also: Guanethidine and hydrochlorothiazide dosage in more detail
Take the missed dose as soon as you remember. However, if it is almost time for your next dose, skip the dose you missed and take only your next regularly scheduled dose. Do not take a double dose of this medication.
Symptoms of a guanethidine and hydrochlorothiazide overdose include low blood pressure (fainting, dizziness, weakness); sleepiness; uncontrollable hand, leg, or arm movements; a slow pulse; low body temperature; diarrhea; increased urination; vomiting, and slow breathing.
Do not let yourself become overheated in hot weather or during exercise, and use caution if you have a fever. These situations increase the effects of guanethidine and hydrochlorothiazide, and you may become very dizzy.Avoid prolonged exposure to sunlight. Hydrochlorothiazide may increase the sensitivity of your skin to sunlight. Use a sunscreen and wear protective clothing when exposure to the sun is unavoidable. Avoid alcohol while taking guanethidine and hydrochlorothiazide. Alcohol, which will further lower your blood pressure, will also increase the drowsiness caused by guanethidine and hydrochlorothiazide and may increase dizziness. Use caution even with small amounts of alcohol.
Avoid a diet high in salt. Too much salt will cause your body to retain water and will decrease the effects of hydrochlorothiazide.
Do not take any over-the-counter cough, cold, allergy, sleep, or diet medications without first asking your doctor or pharmacist. These products will interfere with your guanethidine and hydrochlorothiazide therapy.
Use caution when you are driving, climbing ladders, or performing other hazardous activities until you know how guanethidine and hydrochlorothiazide affects you. If it makes you dizzy or drowsy, avoid these activities.
Tell your doctor and dentist that you are taking this medication before having surgery.
an allergic reaction (difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives);
a very irregular heartbeat;
heart failure (shortness of breath, swelling of ankles or legs, sudden weight gain of 5 pounds or more);
little or no urine;
abnormal bleeding or bruising;
yellow skin or eyes;
uncontrollable hand, arm, or leg movements.
Other, less serious side effects are more likely to occur. Continue to take guanethidine and hydrochlorothiazide and talk to your doctor if you experience
fatigue or drowsiness;
dizziness (avoid standing up too quickly and use caution when performing hazardous activities);
anxiety, depression or nightmares;
diarrhea, nausea, vomiting, or an acid stomach (take guanethidine and hydrochlorothiazide with food or milk if it upsets your stomach);
a stuffy nose or a dry mouth (sucking on ice chips or sugarless hard candy may relieve a dry mouth);
tingling or numbness in your arms, legs, hands, or feet;
muscle weakness or cramps;
increased hunger or thirst;
sensitivity to sunlight; or
Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.
Usual Adult Dose for Hypertension:
Initial dose: 1 tablet orally once a day. Determine dosage by individual titration.Maintenance dose: May increase to 2 tablets orally once a day.
Do not take guanethidine and hydrochlorothiazide if you are taking a monoamine oxidase inhibitor (MAOI), or if you have taken one in the last 14 days. MAOIs, used to treat depression, include isocarboxazid (Marplan), phenelzine (Nardil), and tranylcypromine (Parnate).
Before taking this medication, tell your doctor if you are taking any of the following medicines:
digoxin (Lanoxin) or quinidine (Cardioquin, Quinidex, Quinora, Quinaglute), which will increase the risk of experiencing an irregular heartbeat when taken with guanethidine and hydrochlorothiazide;
barbiturates such as phenobarbital (Luminal, Solfoton), amobarbital (Amytal), and secobarbital (Seconal), which may cause extreme sleepiness or dizziness if taken with guanethidine and hydrochlorothiazide;
narcotic pain relievers such as codeine (Tylenol #3, Tylenol #4, others), propoxyphene (Darvon, Darvocet, Wygesic), oxycodone (Percodan, Percocet, Tylox), meperidine (Demerol), morphine (MS Contin, Duramorph, others), and others, which also may cause extreme sleepiness or dizziness if taken with guanethidine and hydrochlorothiazide;
steroid medications such as hydrocortisone (Hydrocortone, Cortef), prednisone (Deltasone, Orasone), prednisolone (Delta Cortef, Prelone), methylprednisolone (Medrol), betamethasone (Celestone), dexamethasone (Decadron, Hexadrol), and others, which may increase the side effects of hydrochlorothiazide;
prescription and over-the-counter cough, cold, allergy, diet, and sleeping pills, any of which may contain drugs that increase your blood pressure and heart rate and thus decrease the effects of guanethidine;
the cholesterol-lowering drugs cholestyramine (Questran) and colestipol (Colestid), which may decrease the effects of hydrochlorothiazide if they are used together;
nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Motrin, Advil), ketoprofen (Orudis, Orudis, KT, Oruvail), and naproxen (Naprosyn, Anaprox, Aleve), which may also decrease the effects of hydrochlorothiazide;
other commonly used NSAIDs, including diclofenac (Cataflam, Voltaren), etodolac (Lodine), fenoprofen (Nalfon), flurbiprofen (Ansaid), indomethacin (Indocin), ketorolac (Toradol), mefenamic acid (Ponstel), nabumetone (Relafen), oxaprozin (Daypro), piroxicam (Feldene), sulindac (Clinoril), and tolmetin (Tolectin);
oral antidiabetic drugs such as Glipizide (Glucotrol), glyburide (Micronase, Glynase, Diabeta), chlorpropamide (Diabinese), tolazamide (Tolinase) and tolbutamide (Orinase), which may not lower your blood sugar as well during therapy with guanethidine and hydrochlorothiazide (your diabetes therapy may have to be adjusted);
lithium (Lithobid, Eskalith), which should not be taken with hydrochlorothiazide because serious side effects may result; or
other drugs that also lower blood pressure, including acebutolol (Sectral), atenolol (Tenormin), bisoprolol (Zebeta), carteolol (Cartrol), labetalol (Trandate, Normodyne), propranolol (Inderal), pindolol (Visken), timolol (Blocadren), benazepril (Lotensin), enalapril (Vasotec), captopril (Capoten), fosinopril (Monopril), lisinopril (Prinivil, Zestril), moexipril (Univasc), quinapril (Accupril), ramipril (Altace), amlodipine (Norvasc), bepridil (Vascor), diltiazem (Cardizem, Dilacor), felodipine (Plendil), isradipine (Dynacirc), nicardipine (Cardene), nifedipine (Adalat, Procardia), nimodipine (Nimotop), and verapamil (Calan, Verelan, Isoptin).
Drugs other than those listed here may also interact with guanethidine and hydrochlorothiazide or affect your condition. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines.
Guanethidine and hydrochlorothiazide is available with a prescription under the brand name Esimil. Other brand or generic formulations may also be available. Ask your pharmacist any questions you have about this medication, especially if it is new to you.
guanethidine/hydrochlorothiazide strengths are as follows:
Esimil 10 mg/25 mg--round, white scored tablets