Beta-Adrenergic Blocking Agents
Brand & Generic Names
| ATENOLOL & | NADOLOL & |
| CHLORTHALIDONE | BENDROFLUMETHIAZIDE |
| BETAXOLOL & | Normozide |
| CHLORTHALIDONE | PINDOLOL & |
| Co-Betaloc | HYDROCHLOROTHIAZIDE |
| Corzide | PROPRANOLOL & |
| Inderide | HYDROCHLOROTHIAZIDE |
| Inderide LA | Tenoretic |
| LABETALOL & | Timolide |
| HYDROCHLOROTHIAZIDE | TIMOLOL & |
| Lopressor HCT | HYDROCHLOROTHIAZIDE |
| METOPROLOL & | Trandate HCT |
| HYDROCHLOROTHIAZIDE | Viskazide |
BASIC INFORMATION
- Habit forming? No
- Prescription needed? Yes
- Available as generic? Yes
- Drug class: Beta-adrenergic blocker
USES
- Reduces angina attacks.
- Stabilizes irregular heartbeat.
- Lowers blood pressure.
- Reduces frequency of migraine headaches. (Does not relieve headache pain.)
- Other uses prescribed by your doctor.
DOSAGE & USAGE INFORMATION
How to take:
- Tablet, liquid or extended-release capsule — Swallow with liquid.
- If you can’t swallow whole, crumble tablet or open capsule and take with liquid or food. Don’t crush capsule.
When to take:
With meals or immediately after.
If you forget a dose:
Take as soon as you remember. Return to regular schedule, but allow 3 hours between doses.
What drug does:
- Blocks certain actions of sympathetic nervous system.
- Lowers heart’s oxygen requirements.
- Slows nerve impulses through heart.
- Reduces blood vessel contraction in heart, scalp and other body parts.
Time lapse before drug works: 1 to 4 hours.
Don’t take with: Any other medicines, even over-the-counter drugs such as cough and cold medicines, nose drops, diet pills, laxatives or caffeine, without consulting your doctor.
OVERDOSE
- SYMPTOMS: Weakness, slow or weak pulse, blood-pressure drop, fainting, difficulty breathing, convulsions, cold and sweaty skin.
- WHAT TO DO: Dial 0 (operator) or 911 (emergency) for an ambulance or medical help. Then give first aid immediately.
POSSIBLE ADVERSE REACTIONS OR SIDE EFFECTS
SYMPTOMS WHAT TO DO
Life-threatening: Congestive heart Discontinue. Seek failure. emergency treatment.
Common:
- Pulse slower than Discontinue. Call 50 beats per minute. doctor right away.
- Drowsiness, fatigue, Continue. Call doctor numbness or tingling when convenient. of fingers or toes, dizziness, diarrhea, nausea, weakness.
- Cold hands or feet; Continue. Tell doctor dry mouth, eyes and at next visit. skin. Infrequent:
- Hallucinations, Discontinue. Call nightmares, insomnia, doctor right away. headache, difficult breathing, joint pain, anxiety.
- Confusion, reduced Continue. Call doctor alertness, depression, when convenient. impotence.
- Constipation. Continue. Tell doctor at next visit. Rare:
- Rash, sore throat, Discontinue. Call fever. doctor right away.
- Unusual bleeding and Continue. Call doctor bruising; dry, burning when convenient. eyes; impotence.
WARNINGS & PRECAUTIONS
Don’t take if:
- You are allergic to any beta-adrenergic blocker.
- You have asthma.
- You have hay fever symptoms.
- You have taken MAO inhibitors in past 2 weeks.
Before you start, consult your doctor:
- If you have heart disease or poor circulation to the extremities.
- If you have hay fever, asthma, chronic bronchitis, emphysema.
- If you have overactive thyroid function.
- If you have impaired liver or kidney function.
- If you will have surgery within 2 months, including dental surgery, requiring general or spinal anesthesia.
- If you have diabetes or hypoglycemia. Pregnancy: Risk to unborn child outweighs drug benefits. Don’t use. Infants & children: Don’t give to infants or young children unless prescribed and monitored by your physician. Prolonged use: Weakens heart muscle contractions. Skin & sunlight: No age-related problems expected.
Driving or hazardous activities:
Don’t drive or pilot aircraft until you learn how medicine affects you. Don’t work around dangerous machinery. Don’t climb ladders or work in high places. Danger increases if you drink alcohol or take medicine affecting alertness and reflexes.
Discontinuing: Don’t discontinue without consulting doctor. Dose may require gradual reduction if you have taken drug for a long time. Doses of other drugs may also require adjustment.
Others: May mask hypoglycemia.
Possible Interaction with Other Drugs
| GENERIC NAME | COMBINED EFFECT |
| ———————— | ———————– |
| Allopurinol | Decreased allopurinol effect. |
| Aminophylline | Decreased effectiveness of both. |
| Antidepressants, | Dangerous drop in blood pressure. |
| tricyclic (TCA) | Avoid combination unless under |
| medical supervision. | |
| Antidiabetics | Increased antidiabetic effect. |
| Antihistamines | Decreased antihistamine effect. |
| Antihypertensives | Increased antihypertensive effect. |
| Barbiturates | Increased barbiturate effect. |
| Dangerous sedation. | |
| Bumetanide | Increased diuretic effect. |
| Calcium channel | Increased antihypertensive |
| blockers | effect. Dosages of both drugs may |
| require adjustments. | |
| Cholestyramine | Decreased hydrochlorthiazide |
| effect. | |
| Cortisone drugs | Excessive potassium loss that |
| causes dangerous heart rhythms. | |
| Diclofenac | Decreased antihypetensive effect. |
| Digitalis | Excessive potassium loss that causes |
| preparations | dangerous heart rhythms. Can either |
| increase or decrease heart rate. | |
| Improves irregular heartbeat. | |
| Diuretics, thiazide | Increased effect of other thiazide |
| diuretics. | |
| Ethacrynic acid | Increased diuretic effect. |
| Furosemide | Increased diuretic effect. |
| Guanfacine | Increased effect of both drugs. |
| Hypoglycemics, | Decreased ability to |
| oral | lower blood glucose. |
| Indapamide | Increased diuretic effect. |
| Insulin | Decreased ability to lower blood |
| glucose. | |
| Lisinopril | Increased antihypertensive effect. |
| Dosage of each may require | |
| adjustment. | |
| MAO inhibitors | Increased hydrochlorothiazide |
| effect. | |
| Metolazone | Increased diuretic effect. |
| Narcotics | Increased narcotic effect. |
| Dangerous sedation. | |
| Nicardipine | Possible irregular heartbeat and |
| congestive heart failure. | |
| Nicotine | Increased beta blocker effect. |
| Nitrates | Excessive blood pressure drop. |
| Non-steroidal | Decreased anti- |
| anti-inflammatory | inflammatory effect. |
| Phenytoin | Increased betaadrenergic effect. |
| Potassium | Decreased potassium |
| supplements | effect. |
| Probenecid | Decreased probenecid effect. |
| Propafenone | Increased effect of both drugs and |
| increased risk of toxicity. | |
| Quinidine | Slows heart excessively. |
| Reserpine | Increased reserpine effect. |
| Excessive sedation and depression. | |
| Sympathomimetics | Decreased effectiveness of both. |
| Theophylline | Decreased effectiveness of both. |
| Tocainide | May worsen congestive heart |
| failure. | |
| Zinc supplements | Increased need for zinc. |
Possible Interaction with Other Substances
| INTERACTS WITH | COMBINED EFFECT |
| ————— | ————— |
| Alcohol: | Dangerous blood pressure drop. |
| Avoid. | |
| Beverages: | None expected. |
| Cocaine: | Irregular heartbeat, decreased |
| beta-blocker effect. Avoid. | |
| Licorice. | Excessive potassium loss that |
| causes dangerous heart rhythms. | |
| Marijuana: | May increase blood pressure. |
| Tobacco: | May increase blood pressure and |
| make heart work harder. Avoid. |
From the Complete Guide to Pediatric Symptoms, Illness & Medications by H. Winter Griffith, M.D. © 1989 The Putnam Berkley Group, Inc.; electronic rights by Medical Data Exchange
