Procainamide Captopril

Acetazolamide, captopril, ethacrynic acid, furosemide, hydralazine, methazolamide, methyldopa, procainamide, thiazide diuretics, and ticlopidine... 

Acetazolamide, amprenavir, captopril, hydralazine, hydrochlorothiazide, methyldopa, procainamide, quinidine, ticlopidine, and triamterene... 

Autoantibodies to red blood cells and autoimmune hemolytic anemia have been observed in patients treated with numerous drugs, including procainamide, chlor-propaminde, captopril, cefalexin, penicillin, and methyldopa (Logue et al., 1970 Kleinman et al., 1984). Hydralazine- and procainamide-induced autoantibodies may also result in SLE. Approximately 20% of patients administered methyldopa for several weeks for the treatment of essential hypertension developed a dose-related titer and incidence of autoantibodies to erythrocytes, 1% of which presented with hemolytic anemia. Methlydopa does not appear to act as a hapten but appears to act by modifying erythrocyte surface antigens. IgG autoantibodies then develop against the modified erythrocytes. 

Cardiovascular Acetyldigosin, ajmaline, amiodarone, aprindine, bepridil, bezaflbrate, captopril, dinepazide, clopidogrel, coumarins, diazoxide, digoxin, dipyridamole, disopyramide, doxazosin, enalapril, flurbiprofen, fur-oxemide, hydralazine, lisinopril methyldopa, metolazone, nifedipine, phenindione, procainamide, propanolol, propafenone, quinidine, ramapril, spironolactone, thiazide diuretics, ticlopidine, vesnarinone... 

Type III reactions are caused by tissue injury due to immune complexes. The antigen-antibody complexes are usually cleared by the immune system however, repeated contact with antigens can cause the complex to deposit in tissue and result in tissue injury. Serum sickness is the classic example of a Type III reaction. Medications associated with serum sickness include many antibiotics, phenytoin, salicylates, barbiturates, nonsteroidal antiinflammatory drugs, isoniazid, antisera, hydralazine, captopril, and sulfonamides. Procainamide-induced lupus, described in Chapter 16, is also considered a Type III reaction. 

Acebutolol Alpha-methyl-dopa Captopril Carbimazole Chlorpromazine Dihydralazine Fludarabine Hydralazine Infliximab Interferons-alpha Iproniazid Isoniazid Nomifensine Penicillamine D-Penicillamine Practolol Procainamide Propylthiouracil rlL-2 Simvastatin Tienilic acid Tryptophan contaminants Zimeldine Lupus syndrome Autoimmune haemolytic anaemia Pemphigus ANCA-associated vasculitis Lupus syndrome Autoimmune hepatitis Autoimmune haemolytic anaemia Lupus syndrome, ANCA-associated vasculitis Lupus syndrome Wide range of autoimmune diseases Autoimmune hepatitis Lupus syndrome Autoimmune haemolytic anaemia Myasthenia, dermatomyositis Anti-GBM (Goodpasture) disease Oculocutaneomucous syndrome Lupus syndrome ANCA-associated vasculitis Autoimmune thyroiditis Lupus syndrome Autoimmune hepatitis Eosinophilia myalgia syndrome (see section 9.3.5) Guillain-Barre syndrome... 

Noninterfering mexiletine, captopril, dipyridamole, disopyramide, procainamide, propafenone, quinidine, sulfamethoxazole, trimethoprim, verapamil... 

These interaetions are not elearly established, and the reaction appears to he rare and unpredictable. All that can he constructively said is that patients taking both drugs should he very closely monitored for any signs of hypersensitivity (e.g. skin reactions) or low white cell count (sore throat, fever), especially if they have renal impairment. The UK manufacturer of captopril recommends that diffeiential white hlood cell counts should be performed before adding allopurinol, then every 2 weeks during the first 3 months of treatment, and periodically thereafter. Similar caution and advice is given by the UK manufacturers of several other ACE inhibitors. For other possible interactions with ACE inhihitors that might result in an increased risk of leucopenia see also ACE inhihitors + Azathioprine , p.l8 and ACE inhibitors + Procainamide , p.33. 

The combination of captopril or other ACE inhibitors and procainamide possibly increases the risk of lencopenia. No pharmacokinetic interaction occurs between captopril and procainamide. 

Levinson B, Sugerman AA, McKown J. Lack of kinetic interaction of captopril (CP) and procainamide A) in healthy subjects. JC/mP/ja/TMaco/(1985) 25, 460. 

---