Pharmaceutical methods for relief of dysmenorrhea and/or premenstrual syndrome and process
This is a continuation of U.S. Ser. No. 07/452,022 filed Dec. 15, 1989, now U.S. No. 5,037,823, which is a continuation-in-part of U.S. Ser. No. 06/907,698 filed Sep. 15, 1986, now U.S. Pat. No. 4,888,343 issued Dec. 19, 1989. 
     FIELD OF THE INENTION 
     This invention relates to pharmaceutical compositions useful in the treatment of dysmenorrhea and/or premenstral syndrome. 
     BACKGROUND OF INVENTION 
     Dysmenorrhea is a term used to describe painful menstration. the pain may range from minor cramping to intense pain accompanied by diarrhea, nausea and vomiting, with sensations of pelvic heaviness and breast fullness. Premenstral syndrome refers to the tension accruing prior to the onset of menstruation, and is characterized by headaches, nervousness and edema. Once menstruation has begun, there is noticeable polyuria and rapid disappearance of the edema. 
     Pharmaceutical products for the treatment of dysmenorrhea and/or premenstrual syndrom are known in the prior art and have been marketed commercially. Thus, for example, a number of commercially available products contain a combination of acetaminophen and pamabrom or a combination of acetaminophen, pamabrom and pyrilamine maleate. Products of this character do not contain a non-steroidal anti-inflammatory agent, such as ibuprofen or aspirin, which are highly important but not optimal in relieving the symptoms of dysmenorrhea and/or premenstrual syndrom. The acetaminophen used in such products is known to be an effective analgesic but is not generally recognized as exhibiting significant anti-inflammatory properties. 
     There is at least one commercial product containing a non-steroidal anti-inflammatory such as aspirin that is marketed for use in treating dysmenorrhea and/or premenstrual syndrome. Disadvantageously, this product does not contain a reliably effective diuretic which, when combined with an effective NSAID, provides relief of the array of symptoms of dysmenorrhea and/or pemenstrual syndrom. Thus, this product contains a mixture of aspirin, cinnamedrine and caffeine. Cinnamedrine is conventionally recognized as a antispasmodic. Caffeine, although it si recognized as a diuretic, is not a highly potent diuretic. Moreover, the latter has the disadvantage of inducing sleeplessness int eh subjects to whom it is administered, an important consideration for evening utility. 
     Compositions for sue in the treatment of dysmenorrhea, which are disclosed in European Patent Application 0 081 823, are &#34;combinations of analgesics (including prostaglandin synthetase inhibitors such aspirin, indomethacin and ibuprofen), diuretics, antihistamines and antispasmadics.&#34; The invention of this European Patent Application is said to reside int also incorporating 5-500 mg dextromethorophan hydrochloride with one or more of: a conventional diuretic such as ammonium chloride, pamaborm and hydrochlorothiazide; a conventional antihistamine such as pyrilamine maleat; a conventional antispasmodic, for example, cinnamedrine, or a conventional analgesic such as, for example, aspirin, acetaminophen, indomethacin, ibuprofen or naproxen. 
     G. F. Shah et al, Effect of Nonsteroidal Antiinflammatory Drugs (NSAIDS) on Diuretic Property of Hydrochlorothiazide, Indian J. Parm., 17:224-8 (1985), studied the effects of several NSAIDs including ibuprofen on hydrochylorotheiazide (HCTZ) induced changes in urinary volume, sodium, potassium and creatinine excretion, inconscious rats. Shah et al concluded that the diuretic effect as well as the increased urinary sodium and potassium excretion elicited by HCTZ at 2.5 and 5 mg/kg were inhibited after oral administration of NSAIDs such as indomethacin, oxyphenbutazone, ibuprofen and naproxen, in doses which inhibited the rate carrageenin induced hind paw oedema. 
     Shah et al reports that of the NSAIDs tested, ibuprofen was found to be the most potent in antagonizing diuretic and natriuretic activity. Thus, a dose of 12.5 mg/kg ibuprofen inhibited the diuretic activity of 5 mg/kg HCTZ, while 25 mg/kg ibuprofen significantly antagonized the diuretic activity of 10 mg/kg HCTZ. It is further seen from Table 4 of Shah et al that as the ratio of ibuprofen to HCTZ increased at a constant dose of HCTZ, there was a concomitant reduction int h diuretic activity. For example, at 10 mg/kg KCTZ, the reported diuretic activity is 2.2±0.16, while at 10 mg/kg HTZ and 25 mg/kg ibuprofen, the diuretic activity was 1.6-0.07, a reduction of about 28%. Similarly, Shah et al observed like reductions in natriuretic activity. 
     It is noteworthy that Shah et al administered each of the ibuprofen and the HCTZ in a gum arabic suspension. As pointed out in bowman &amp; Rand, Textbook of Pharmacology, p. 40.10 (2nd Edition 1980), the activity of HCTZ is preparation-dependent. Accordingly, Shah et al&#39;s observations are not predictive of the performance of a tablet comprising ibuprofen and HCTZ. 
     SUMMARY OF THE INVENTION 
     The present invention involves a composition which contains as the only pharmaceutically active ingredients (a) a non-steroidal anti-inflammatory selected from the group consisting of aspirin and ibuprofen, (b) a diuretic selected from the group consisting of pamaborm and hydrochlorothiazide, and, optionally, (c) an antihistamine, preferably pyrilamine or a pharmaceutically acceptable salt thereof, these ingredients being present at a level in these compositions to afford relief from the symptoms of dysmenorrhea and/or pemenstrual syndrome when said compositions are administered to subjects exhibiting these conditions. Pyrilamine has been shown to be a safe and effective calmative, relieving the tension of dysmenorrhea and/or premenstrual syndrome. The compositions of the present invention advantageously contain an effective anti-inflammatory agent, a reliably effective diuretic, and, optionally, an effective calmative. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The non-steroidal anti-inflammatory agents useful in the compositions herein disclosed are ibuprofen or aspirin. Combinations of these drugs may also be employed but ordinarily either one or the other will be utilized. The quantity of said anti-inflammatory agent contained in the present composition may be expressed in the form of the daily average dose for this agent, which will vary with anti-inflammatory drug selected. Generally for ibuprofen this will be about 100 to about 2000 mg/day with the preferred range being about 200 to about 1200 mg/day. Int h case of aspirin the general average daily dose will be about 200 mg/day to about 5 gm/day, the preferred range being about 500 to about 2000 mg/day. 
     In similar fashion, the quantity of the particular diuretics of use in the present invention and contained in the present products may also be expressed on the basis of the daily average dose for the diuretics (i.e. pamabrom, hydrochlorothiazide or combination thereof), which also will vary with the particular diuretic selected. When the diuretic is hydrochlorothiazide the general average daily does of this drug provided by the product will be from about 5 to about 250 mg/day and in the case of pamabrom from about 5 to about 500 mg/day. In both cases the preferred range is about 25 to about 200 mg/day. 
     When the antihistamine (i.e. pyrilamine or its pharmaceutically acceptable salts) is employed in the practice of this invention its level of use is also expressible on the basis of its daily average does. In this case, the daily average dose will be from about 15 mg to about 400 mg. However, the preferred daily average dose for the antihistamine will fall in the range of from about 30 mg to about 200 mg. 
     Any of the pharmaceutically acceptable salts of pyrilamine may be utilized in carrying forward the purpose of this invention. By way of example mention may be made of pyrilamine maleate citrate, hydrochloride or sulfate. 
     The products of this invention will generally be administered in a convenient unit dosage form, preferably in solid dose form such as a tablet, powder, capsule, and the like. The quantity of the respective ingredients that may be contained in this unit dosage form is given in the table below: 
     
         ______________________________________                                    
        Unit Dosage Form                                                  
        General Range in mg                                               
                     Preferred Range in mg                                
______________________________________                                    
Ibuprofen 50 mg to 800 mg                                                 
                         100 mg to 400 mg                                 
Aspirin   50 mg to 975 mg                                                 
                         150 mg to 650 mg                                 
Pamabrom   1 mg to 100 mg                                                 
                          5 mg to 50 mg                                   
Hydrochloro-                                                              
           1 mg to 50 mg  5 mg to 25 mg                                   
thiazide                                                                  
Pyrilamine Salt                                                           
           0 mg to 100 mg                                                 
                          15 mg to 50 mg                                  
______________________________________                                    
 
    
     Optimally each unit dosage form will contain form about 200 mg to about 400 mg of ibuprofen or from about 325 to 500 mg of aspirin. 
     The prior art Shah et al article demonstrates significantly antagonized diuretic activity of HCTZ when administered in the presence of ibuprofen at ibuprofen/HCTZ ratios of 0.625:1 to 10:1. Surprisingly and unexpectedly, ti has been found by Applicants that the diuretic activity antagonism did not worsen as anticipated at higher ratios of ibuprofen to HCTZ, as demonstrated hereinafter with regard to Examples 8 and 9. In the compositions of the present invention, the ratio of ibuprofen to HCTZ is above about 16:1, preferably from about 16:1 to 64:1, most preferably from about 24:1 to 48:1. 
     In addition to the pharmacologically active ingredients mentioned above, the products of this invention may also contain other excipients. These to a large extent will depend on the nature of the unit dosage form selected for dispensing the present composition. 
     The present products may be made into capsules, tablets, powders, caplets and may be film coated, energy coated or formulated into sustained release dosage forms or liquid dosage compositions. When formed into tablets or caplets they may contain adjuvants that facilitate the tableting of the product or enhance its elegance or dissolution rates. Generally illustrative of the adjuvants that may be contained in the various dosage forms encompassed in the present invention are: disintegrating agents, ginders, lubricants, filers, glidents, surfactants, flavoring agents, sweeteners, solvents, liquid carriers, suspending agents, preservatives, etc. More particularly the adjuvants that may be contained in the various dosage forms over and above the active ingredients are as follows: 
     Capplet and Tablet: Cellulose, lactose, corn starch, stearic acid, water, gelatin, talc, Sterotex, magnesium stearate, terra alba, sucrose, Cab-O-Sil, acacia, etc. 
     A capsule: spray dried lactose, dimethylsiloxane, coren starch, magnesium stearate, sucrose, Cab-o-Sil, etc. 
     Liquid Dosage Forms: polyethylene glycol, sucrose, Povidone, sodium citrate, citric acid, flavor, color, quinine, water, etc. 
     Sustained release compositions may contain such things as glyceryl monostearate, glyceryl disterate, cellulose ethers such as hydroxypropyl methylcellulose and hydroxy propylcellulose, stearic acid, etc. 
     In general, the products of the present invention may be prepared using the standard technique well known to those skilled in this at, e.g., standard tableting or capsule preparing procedures. However, when pamabrom is utilized as the diuretic and ibuprofen as the non-steroidal anti-inflammatory it has been found advantageous to granulate the pamabrom before mixing it with the Ibuprofen. These ingredients, when mixed together in standard procedures, tend to form esthetic mixtures with the result that tablets containing such a mixture become soft upon exposure to stress testing conditions and capsules turned pasty. In addition both of these dosage forms also changed color form white to yellow or organ when prepared using the standard procedures. 
     When an antihistamine, e.g., pyrilamine maleate, is used in conjunction with the pamagrom and ibuprofen, it si often advantageous to granulate the combination of pamabrom and antihistamine before mixing this combination with the ibuprofen. This mixture, with or without other adjuvants may then be used to prepare the dosage forms, e.g., capsule, tablets. 
     The products of this invention may be administered using a variety of regimens. Ordinarily the acceptable daily dose will be provided by taking the product twice three times or four times a day. 
     The following examples are given to further illustrate the present invention. It is to be understood, however, that the invention is not limited thereto. 
     The following are the chemical definitions of the materials used in the Examples and identified therein by their trade designations: 
     Advice PH 101 and 102: Microcrystalline Cellulose, FMC Inc. 
     Starch 1500: Pregelatinized starch, Colorcon Inc., West Point, Pa. 
     Silicone Oil: Dimethicone (U.S.P.), Dimethylpolysiloxane 350 CS, Dow Corning 
     Tween 80: Polysorbate 80 (CTFA-Cosmetic Ingredient Dictionary, Third Edition, p. 247) 
     Cab-O-Sil: Fumed Silica, Cabot, Inc. 
     Povidone: Polyvinyl pyrroglidone, GAF corp. 
     Crospovidone XL10: Cross linked Polyvinyypyrrolidone, GAF corp. 
     The &#34;Ibuprofen Granulation&#34; used in Examples 5 and 6 below is prepared by first mixing ibuprofen (200 mg) and corn starch (50 mg). An aqueous granulating solution, prepared containing Povidone K29-32 (6mg), Avicel PH 101 (41.5 mg) and Crospovidone XL-10 (1.5 mg), was used to granulate the ibuprofen/starch mixture. 
     EXAMPLE 1 
     Ibuprofen/Pamabrom/Pyrilamine Maleate: Capsules Formula CE 3375-70 
     
         ______________________________________                                    
Ingredients       Amount Per Dose                                         
______________________________________                                    
a.      Ibuprofen     150.00 mg                                           
b.      Pamabrom       25.00 mg                                           
c.      Pyrilamine Maleate                                                
                       15.00 mg                                           
d.      Avicel pH 101  50.00 mg                                           
e.      Starch 1500   117.50 mg                                           
f.      Silicon Oil    2.00 mg                                            
g.      Tween 80       0.50 mg                                            
h.      Cab-O-Sil      0.25 mg                                            
                      360.25 mg                                           
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     Method 
     A. Blend b, d and 30 mg e 
     B. Dissolve c in water and use to granulate A, then dry p0 C. Blend 87.5 mg e, f and g 
     D. Blend B, C, a and h. Fill into size # 1 capsules 
     EXAMPLE 2 
     Ibuprofen/Pamabrom: Capsules Formula CS 3570-05 
     
         ______________________________________                                    
Ingredients     Amount Per Dose                                           
______________________________________                                    
a.      Ibuprofen   150.00 mg                                             
b.      Pamabrom    25.00 mg                                              
c.      Avicel pH 101                                                     
                    82.50 mg                                              
d.      Starch 1500 90.00 mg                                              
e.      Silicon Oil  2.00 mg                                              
f.      Tween 80     0.50 mg                                              
                    350.00 mg                                             
______________________________________                                    
 
    
     method 
     A. Mix b, 50 mg d and 42.5 mg c, granulate with water and dry 
     B. Mix 40 mg d, e and f 
     C. Mix A, B, a and 40 mg c 
     D. Fill C into size # 1 capsules 
     EXAMPLES 3 and 4 
     Ibuprofen/Hdyrochlorothiazide HCl: Capsule 
     
         ______________________________________                                    
             Example 3     Example 4                                      
             Formula CS 3570-14                                           
                           Formula CS 3570-31                             
Ingredients  Amount Per Dose                                              
                           Amount Per Dose                                
______________________________________                                    
a.  Ibuprofen    200.00 mg     300.00 mg                                  
b.  Hydrochlorothia-                                                      
                 12.50 mg      12.50 mg                                   
    zide HCI                                                              
c.  Starch 1500  134.50 mg     183.50 mg                                  
d.  Silicon Oil  2.00 mg       2.80 mg                                    
e.  Tween 80     0.50 mg       0.70 mg                                    
f.  Cab-O-Sil    0.50 mg       0.50 mg                                    
                 350.00 mg     500.00 mg                                  
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     Method 
     A. Blend all ingredients 
     B. Fill blends or CS3570-14 into size # 1 capsules and for CS3570-31 into size # 0 capsules. 
     EXAMPLE 5 
     Ibuprofen/Pamabrom/Pyrilamine Maleate Tablets 
     
         ______________________________________                                    
                     Formula CS 3570-34                                   
Ingredients          Amount Per Dose                                      
______________________________________                                    
a.    Pamabrom           25.00 mg                                         
b.    Pyrilamine Maleate 15.00 mg                                         
c.    Starch 1500        75.00 mg                                         
d.    Povidone, USP (K29-32)                                              
                          0.75 mg                                         
e.    Hydroxypropyl methycellulose                                        
                          4.11 mg                                         
      E5-Premium                                                          
f.    Propylene Glycol    0.90 mg                                         
g.    Ibuprofen Granulation                                               
                         224.24 mg                                        
      (Equivalent to 150 mg                                               
      Ibuprofen)                                                          
h.    Silicon Oil         2.00 mg                                         
i.    Tween 80            0.50 mg                                         
j.    Starch 1500        35.00 mg                                         
                         382.50 mg                                        
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     Method 
     A. Blend a, b and c, granulate with water and dry 
     B. Dissolved d, e and f in water and use to spray coat A 
     C. Blend h, i and j 
     D. Blend B, C and g and compress into tablet 
     EXAMPLE 6 
     Ibuprofen/Pamabrom/Pyrilamine Maleate Tablets 
     
         ______________________________________                                    
                     Formula CS 3570-32                                   
Ingredients          Amount Per Dose                                      
______________________________________                                    
a.    Pamabrom           25.00 mg                                         
b.    Pyrilamine Maleate 15.00 mg                                         
c.    Avicel PH 101      50.00 mg                                         
d.    Povidone, USP (K29-32)                                              
                          6.74 mg                                         
e.    Hydroxypropyl methylcellu-                                          
                          6.63 mg                                         
      lose E5-Premium                                                     
f.    Propylene Glycol    1.24 mg                                         
g.    Ibuprofen Granulation                                               
                         224.24 mg                                        
      (Equivalent to 150 mg                                               
      Ibuprofen)                                                          
h.    Starch 1500        35.00 mg                                         
i.    Silicone Oil        2.00 mg                                         
j.    Tween 80            0.50 mg                                         
                         366.35 mg                                        
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     Method 
     A. Blend a, b and c 
     B. Dissolve 5.6 mg d in water and use to granulate A, then dry 
     C. Dissolve 1.14 mg d, e and f in water and use to spray coat B 
     D. Blend h, i and j 
     E. Bland C, D and g and compress into tablet 
     EXAMPLE 7 
     Ibuprofen/Hydrochlorothiazide HC1 Tablets 
     
         ______________________________________                                    
                      Formula CS 3570-15                                  
Ingredients           Amount Per Dose                                     
______________________________________                                    
a.    Ibuprofen           200.00 mg                                       
b.    Corn Starch NF      50.00 mg                                        
c.    Povidone, K29-32    6.00 mg                                         
d.    Avicel PH 101       41.50 mg                                        
e.    Avicel PH 102       136.50 mg                                       
f.    Hydrochlorothiazide HCl, USP                                        
                          12.50 mg                                        
g.    Crospovidone XL10   2.50 mg                                         
h.    Cab-O-Sil           0.50 mg                                         
i.    Magnesium Stearate  0.50 mg                                         
                          450.00 mg                                       
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     Method 
     A. Blend all ingredients geometrically 
     B. Compress into tablets 
     EXAMPLE 8 
     A preclinical diuretic efficacy study was conducted in two stages (Experiments A and B), the experiments being run fifteen days apart and each experiment lasting two days. 
     In Experiment A, five doses of hydrochlorothiazide (HCTZ) ranging from 0.25 to 4 mg/kg were tested, while in Experiment B, four doses of HCTZ ranging from 1.5 to 12 mg/kg were used and coadministered with a constant dose of 96 mg/kg ibuprofen. 
     Also tested in Experiment A was a control containing no actives (vehicle only), and also tested in Experiment B was a first control containing no actives and a second control containing 96 mg/kg ibuprofen. 
     Ten male Wistar rats were used per dose in each experiment. the rate were fasted overnight prior to testing and during testing. After the study dose (or vehicle) was administered, each animal was given a hydrating does of normal saline (30 ml/kg). Each rat was placed in an individual cage and urine collected for five hours. Total urinary volume, total urinary sodium and potassium excretion, and urinary pH were determined, which parameters were analyzed as ml/kg body weight, mEq/kg body weight, and pH, respectively. 
     The results of the tests are provided below. 
     
         ______________________________________                                    
Experiment A                                                              
HCTZ     Volume   Na          K                                           
(mg/kg)  (ml/kg)  (mEg/kg)    (mEg/kg)                                    
                                      pH                                  
______________________________________                                    
0-       18.69    2.53        0.73    5.72                                
0.25     23.17    3.47        0.80    5.78                                
0.50     22.01    3.33        0.95    5.76                                
1.0      28.61    4.09        0.97    5.61                                
2.0      32.91    5.20        1.16    5.26                                
4.0      37.04    5.29        1.58    5.64                                
______________________________________                                    
Experiment B                                                              
HCTZ (mg/kg) w/96                                                         
             Volume   Na        K                                         
mg/kg Ibuprofen                                                           
             (ml/kg)  (mEg/kg)  (mEg/kg)                                  
                                        pH                                
______________________________________                                    
0- w/o Ibuprofen                                                          
             20.24    2.93      0.80    6.11                              
0- w/Ibuprofen                                                            
             12.61    1.49      0.55    6.22                              
 1.5         22.98    3.57      1.19    6.06                              
 3.0         17.08    2.92      0.99    5.98                              
 6.0         22.97    3.66      1.08    5.75                              
12.0         26.37    4.42      1.22    6.05                              
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     The urinary excretion data from Experiment A demonstrate a clear-cut dose response for HCTZ. The data collected for the two controls (--O--mg HCTZ w/o ibuprofen and --O--mg HCTZ w/ibuprofen) in Experiment B illustrate the extent to which ibuprofen itself causes urinary concentration. The data reflect urinary excretion of sodium and potassium, and reduced volume. Unexpectedly, when combined with ibuprofen, the diuretic efficacy of HCTZ is exhibited as increased urinary volume, as well as the content of sodium and potassium. In Shah et al, a significant inhibition of diuretic was observed at the 5:1 ibuprofen/HCTZ ratio. To the contrary, in these studies above the anti diuretic efficacy of ibuprofen was significantly offset at ratios of ibuprofen to HCTZ of 16:1 to 64:1. 
     EXAMPLE 9 
     A single blind, randomized, four-treatment, four-period crossover study of ibuprofen and hydrochlorothiazide (HCTZ) interaction was conducted with 16 female human adults. The study medications were: (a) a placebo, (b) 12.5 mg HCTZ, (c) 400 mg ibuprofen, and (d) in combination, 400 mg ibuprofen and 12.5 mg HCTZ (32:1 ibuprofen/HCTZ ratio). 
     Alcohol consumption was not permitted for 48 hours before dosing; caffeine was restricted for 24 hours before dosing. The test subjects were holed to a controlled diet with fluid intake, sodium and potassium restricted. 
     Urine was collected and pooled for 24 hours prior to each drug, and was collected voluntarily from the test subjects at 1, 2, 3, 4, 5, 6, 9, 12, 15 and 24 l hours post treatment. 
     The 6- and 24-hours urinary excretion data is reported below. 
     
         ______________________________________                                    
              Urine     Na        K                                       
              Volume    Excretion Excretion                               
Medication    (ml)      (mEg)     (mEg)                                   
______________________________________                                    
Cumulative 6-Hour Urinary Excretion                                       
(a)  Placebo       935      44      14.2                                  
(b)  12.5 mg HCTZ 1405      98      19.3                                  
(c)  400 mg Ibuprofen                                                     
                   799      29      11.9                                  
(d)  400 mg Ibuprofen                                                     
                  1165      76      17.7                                  
     12.5 mg HCTZ                                                         
Cumulative 24-Hour Urinary Excretion                                      
(a)  Placebo      2172      157     45.0                                  
(b)  12.5 mg HCTZ 2681      193     45.5                                  
(c)  400 mg Ibuprofen                                                     
                  2078      138     39.5                                  
(d)  400 mg Ibuprofen                                                     
                  2641      190     43.5                                  
     12.5 mg HCTZ                                                         
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     Shah et al observed approximately a 25% decrease in diuretic activity at ibuprofen/HCTZ ratios of 5:1 and 10:1. Given a typical dose response, one of ordinary skill in the art would anticipate logically that inhibition of urinary activity would be greater as the ibuprofen/HCTZ ratio increased. Unexpectedly, th data above demonstrate that the anticipated dose response does not occur. Thus, at the end of the 6-hour period, the suppression in urine volume was only 17%. After 24 hours the urine output of those test subjects taking the ibuprofen/HCTZ medication was essentially no different from those taking HCTZ only--up about 23% compared to placebo. Those test subjects taking ibuprofen along had a suppression in urine output of 12% as compared to placebo over the 24-hour period. Similarly, after 24 hours the sodium excretion level for the ibuprofen/HCTZ dosing is about the same as or HCTZ along, while ibuprofen along had a 34% decrease, all as compared to the placebo. 
     Extrapolation of the data in Shah et al would suggest total inhibition of HCTZ-induced natriuresis at the 32:1 ibuprofen/HCTZ ratio. Unexpectedly, this was clearly not the case in the clinical studies reported on above. Moreover, the excretion of Na +   without concomitant equivalent loss of K +   as observed herein provides a safety advantage of the ibuprofen/HCTZ combination reported on above.