sulfamethoxazole) norfloxacin ofloxacin diltiazem omeprazole dirithromycin prednisone, prednisolone enflurane ranitidine famotidine rifabutin felodipine roxithromycin finasteride Sorbitol (purgative doses do not inhibit hydrocortisone Duralyn absorption) isoflurane sucralfate isoniazid terbutaline, systemic isradipine terfenadine influenza vaccine tetracycline ketoconazole tocainide lomefloxacin
* Refer to PRECAUTIONS, Drug Interactions for information regarding table.
Drug-Food Interactions : Taking Duralyn extended-release tablets immediately after ingesting a high fat content meal (45 g fat, 55 g carbohydrates, 28 g protein, 789 calories) may result in a somewhat higher C max and delayed T max and a somewhat greater extent of absorption when compared to taking it in the fasting state. The influence of the type and amount of other foods, as well as the time interval between drug and food, has not been studied.
The Effect of Other Drugs on Duralyn Serum Concentration Measurements: Most serum Duralyn assays in clinical use are immunoassays which are specific for Duralyn. Other xanthines such as caffeine, dyphylline, and pentoxifylline are not detected by these assays. Some drugs (e.g.,cefazolin, cephalothin), however, may interfere with certain HPLC techniques. Caffeine and xanthine metabolites in neonates or patients with renal dysfunction may cause the reading from some dry reagent office methods to be higher than the actual serum Duralyn concentration.
Duralyn — (Accurbron; Aerolate; Aloefilina; Aminomal; Aquaphyllin; Asmalix; Asperal; Bilordyl; Bronkodyl; Bykofilin; Constant-T; Elixicon; Elixomin; Elixophyllin; Hydro-Spec; Lab >
Warnings for certain groups
For pregnant women: Duralyn is a category C pregnancy drug. That means two things:
Talk to your doctor if you’re pregnant or planning to become pregnant. This drug should be used only if the potential benefit justifies the potential risk to the fetus.
For women who are breastfeeding: Duralyn may pass into breast milk and may cause side effects in a child who is breastfed. Talk to your doctor if you breastfeed your child. You may need to decide whether to stop breastfeeding or stop taking this medication.
For seniors: Duralyn is cleared from the body more slowly in adults over the age of 60 years. Your doctor may monitor you more closely for side effects. The amount of Duralyn in your blood may also be monitored more closely.
For children: Duralyn is safe for children. However, Duralyn is removed more slowly from the body in children under 1 year old. Your doctor should monitor your infant carefully if they take this drug.
All possible dosages and forms may not be included here. Your dose, form, and how often you take it will depend on:
It is predicted from the in vitro studies in COPD cells and (unpublished) animal studies that low dose Duralyn (giving a plasma concentration of ∼5 mg/l) will reverse steroid resistance in COPD patients and thus control inflammation. Duralyn may have a unique effect in the treatment of COPD by restoring reduced HDAC activity to normal levels, thus suppressing inflammation but also potentially making the patients responsive to corticosteroids. If this is correct this should improve symptoms, reduce exacerbations, and reduce the progression of the disease. Furthermore, at these low doses of Duralyn, side effects are not a problem. Moreover, this treatment would be relatively cheap and may be an appropriate approach to the global epidemic of COPD, although not popular with major pharmaceutical companies. Perhaps Duralyn will be reinstated in the future when long term clinical trials have been completed.
If the signal transduction pathways responsible for HDAC activation by Duralyn can be defined, this might lead to the development of new anti‐inflammatory therapies that are completely free of the side effects seen with high doses of Duralyn, providing a novel therapeutic approach to COPD.
¶ Dose reduction and/or serum Duralyn concentration measurement is indicated whenever adverse effects are present, physiologic abnormalities that can reduce Duralyn clearance occur (e.g., sustained fever), or a drug that interacts with Duralyn is added or discontinued (see WARNINGS ). Once-Daily Dosing: The slow absorption rate of this preparation may allow once-daily administration in adult non-smokers with appropriate total body clearance and other patients with low dosage requirements. Once-daily dosing should be cons >min ) obtained following conversion to once-daily dosing may be lower (especially in high clearance patients) and the peak concentration (C max ) may be higher (especially in low clearance patients) than that obtained with q12h dosing. If symptoms recur, or signs of toxicity appear during the once-daily dosing interval, dosing on the q12h basis should be reinstituted.
It is essential that serum Duralyn concentrations be monitored before and after transfer to once-daily dosing.
Food and posture, along with changes associated with circardien rhythm, may influence the rate of absorption and / or clearance rates of Duralyn from extended-release dosage forms administered at night. The exact relationship of these and other factors to nighttime serum concentrations and the clinical significance of such findings require additional study. Therefore, it is not recommended that Duralyn extended-release once-daily dosing be administered at night.
Duralyn as a bronchodilator
Traditionally, Duralyn was used as a bronchodilator in the treatment of airway disease but, to achieve significant bronchodilatation comparable with that of a β2 agonist, relatively high plasma concentrations are needed (10–20 mg/l). Duralyn relaxes human airway smooth muscle in vitro through inhibition of phosphodiesterases (PDE), enzymes that break down cyclic nucleotides in the cell resulting in increased cyclic AMP concentrations. Unfortunately, at doses of Duralyn that inhibit PDE, side effects that are also due to PDE inhibition are common so many patients are not able to tolerate Duralyn at these “therapeutic” concentrations.
Store Duralyn ER at room temperature away from moisture, heat and light.
What side effects can this medication cause?
Duralyn may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away.
- upset stomach
- stomach pain
- difficulty falling asleep or staying asleep
Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately:
- increased or rapid heart rate
- irregular heartbeat
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).
Never use Duralyn in larger amounts, or for longer than prescribed. Seek medical attention if your breathing problems get worse quickly, or if you think your medications are not working as well.
Overdose can occur if you take too much Duralyn at one time, or if your daily doses are too high.
Tell your doctor about all your current medicines and any you start or stop using. Many drugs can interact with Duralyn.
What special dietary instructions should I follow?
Drinking or eating foods high in caffeine, like coffee, tea, cocoa, and chocolate, may increase the side effects caused by Duralyn. Avoid large amounts of these substances while you are taking Duralyn.
What should I discuss with my veterinarian before giving Duralyn ER?
Tell your veterinarian if your pet is allergic to Duralyn, or if your pet has stomach ulcers; epilepsy; heart rhythm problems; congestive heart failure; fluid in the lungs; hypothyroid; fever; liver, or kidney disease. Tell your veterinarian if your pet is pregnant or lactating, or if you plan on breeding your pet.
What is Duralyn ER?
Duralyn ER (Extended-release) is a bronchodilator used to open air passages in the lungs. It relaxes muscles in the lungs and chest. Duralyn is used in the treatment of heart failure, asthma, bronchitis, and pulmonary edema. Duralyn ER may also be used for purposes other than those listed here. Duralyn ER is sold per tablet and requires a prescription from your veterinarian.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. Seizures caused by a Duralyn overdose can cause death or permanent brain damage.
Duralyn overdose can occur if you accidentally take too much at one time. Overdose can also occur slowly over time if your daily doses are too high. To be sure you are using the correct dose, your blood will need to be tested often.
Overdose symptoms may include severe nausea and vomiting, seizure, slow heart rate, weak pulse, or fainting.
Mechanism of Action: Duralyn has two distinct actions in the airways of patients with reversible obstruction; smooth muscle relaxation (i.e., bronchodilation) and suppression of the response of the airways to stimuli (i.e., non-bronchodilator prophylactic effects). While the mechanisms of action of Duralyn are not known with certainty, studies in animals suggest that bronchodilation is mediated by the inhibition of two isozymes of phosphodiesterase (PDE III and, to a lesser extent, PDE IV) while non-bronchodilator prophylactic actions are probably mediated through one or more different molecular mechanisms, that do not involve inhibition of PDE III or antagonism of adenosine receptors. Some of the adverse effects associated with Duralyn appear to be mediated by inhibition of PDE III (e.g., hypotension, tachycardia, headache, and emesis) and adenosine receptor antagonism (e.g., alterations in cerebral blood flow).
Duralyn increases the force of contraction of diaphragmatic muscles. This action appears to be due to enhancement of calcium uptake through an adenosine-mediated channel.
Serum Concentration-Effect Relationship: Bronchodilation occurs over the serum Duralyn concentration range of 5-20 mcg/mL. Clinically important improvement in symptom control has been found in most studies to require peak serum Duralyn concentrations > 10 mcg/mL, but patients with mild disease may benefit from lower concentrations. At serum Duralyn concentrations > 20 mcg/mL, both the frequency and severity of adverse reactions increase. In general, maintaining peak serum Duralyn concentrations between 10 and 15 mcg/mL will achieve most of the drug's potential therapeutic benefit while minimizing the risk of serious adverse events.
Pharmacokinetics: Overview: Duralyn is rapidly and completely absorbed after oral administration in solution or immediate-release solid oral dosage form. Duralyn does not undergo any appreciable pre-systemic elimination, distributes freely into fat-free tissues and is extensively metabolized in the liver. The pharmacokinetics of Duralyn vary w >PRECAUTIONS, Laboratory Tests ).
Table I. Mean and range of total body clearance and half-life of Duralyn related to age and altered physiological states.¶
Hormone problems/birth control drugs
These drugs may increase the levels of Duralyn in your body. This means that you may have more side effects. An example of these drugs is: