RHEUMATOID ARTHRITIS-Contd...
Second Line Drugs
Unlike drugs like aspirin and NSAIDs which are considered as fast-acting and first-line drugs these drugs are said to be slow-acting anti-rheumatic drugs(SAARD) or disease-modifying anti-rheumatic drugs (DMARDs).
When a patient suffers from sustained disabilities with RA only an anti-inflammatory course is not sufficient. The course of the disease should be modified to ease the disability. This is possible with second-line drugs like hydroxychloroquine, methotrexate, gold compounds, penicillamine, and sulfasalazine. These drugs are used as an adjuvant along with the anti-inflammatory treatments.
These drugs are acting by delaying or modifying the development of the disease. Therapeutic effects may take several months. Careful monitoring of the patients must be necessary because of the serious side effects.
In general these drugs are used along with anti-inflammatory drugs. But some doctors may initiate with these drugs alone and interchange them if they found one drug is ineffective. The ineffective drug should be discontinued before changing to other drugs.Initiating a second-line drug is possible if the patient is not tolerating anti-inflammatory drugs and their prolonged may result in some possible side effects. Yet these drugs too show potential side effects.
1.Hydroxychloroquine
The dosage is started with 200mg twice daily (400mg/day) or 6.5mg/kg whichever is less. It is possible as per the condition the daily dose can be reduced to 200mg once daily.
The patients should be taking care of the following side effects:-
1. Nausea and epigastric pain is possible but not seriously
2. Rare effects on eyes, skin, CNS, and bonemarrow are possible on the recommended dosage
3. Hydroxychloroquine causes retinal damage and hence visual checkup is recommended every 3 to 6 months by an eye specialist.
It is highly advisable to discontinue the medicine if the first sign of the retinal damage is notified.
4. Corneal damages can be reversible but the retinopathy is irreversible.
2.Methotrexate
As methotrexate acts faster than other second-line drugs some physicians are considering it as a first-line drug yet it is somehow slower than anti-inflammatory drugs.
Methotrexate is a folic acid antagonist and is used in many neoplastic disease treatments.
The initial weekly doses are 5 to 10 mg. This can be divided as twice-daily doses but is not safer and much beneficial.
The dosage can be slowly increased to 15 to 20 mg every 3 to 6 weeks.
Intramuscular dosage also available if the oral route is ineffective or may produce gastric trouble.I.M.dosage is once per month.
The following precautions must be taken:-
Aspirin may increase the toxicity of methotrexate by delaying its excretion. Hence aspirin should not be used with it.
Adverse Effects
1. Gastric effects like nausea, anorexia, stomach cramps, and ulcers)
2.Bone marrow suppressions
3.Liver damage
4. Hypersensitivity reactions lead to pneumonitis
5. Rarely pneumonia and chickenpox may precipitate as the drug is immunosuppressive.
6.Monitor RBC, WBC, and platelet counts.
3.Gold Compounds
Gold compounds are proved as very effective second-line drugs in relieving RA by delay progressions of joint erosions.
a)Gold Sodiumthiomalate i.m.injection
b)Aurothioglucose i.m.injection
A test dose of 10mg is given followed by 25mg of the initial weekly dose for two weeks.
After that the dose can be increased to 50mg per week for 20 weeks can be given.
Once there is an expected effect occur the treatment should be continued with the same 50 mg dosage with 2 weeks intervals followed by every three weeks and then to reach every month for 3 to 6 months.
The treatments should continue as a monthly therapy. Abrupt discontinue of the treatment may result in a relapse of RA which may not respond again to gold therapy.
Side Effects
1.Proteinuria
2.Blood dyscrasias
3.Rashes
4.Leucopenia
5.Thrombocytopenia
6.Aplastic anemia
7.Anaphylaxis
8.Angioneurotic edema
9.Glossitis
10.Interstitial pneumonitis
11. Gold Sodium thiomalate because of its water solubility can produce vasodilation, hypotension, and syncope. These effects do not occur with aurothioglucose which is fat-soluble.
c)Auranofin(Oral)
This drug is orally active, less effective, and less toxic.
The initial dose is 3 mg twice a day or 6 mg once a day for six months.
If no effect the dose can be increased to 3 mg three times daily or 9 mg once daily.
Still there is no effect reached auranofin should be discontinued.
Side Effects
1.Diarrhea, stomach pain usually reversible
2. Rash and stomatitis also reversible
3. Proteinuria also reversible
4.Rarely bone marrow suppression and renal toxicity.
4.Sulphasalazine
Sulphasalazine is a sulphonamide derivative used as an anti-RA drug widely in many countries.
It is a very effective drug
It slows the progression of joint damage
It can be given orally.
The dose is 0.5mg twice daily.
The dose is slowly increased by 0.5mg every week up to 2 to 3 gram /day in divided doses.
Side Effects
1.G.I.Distress
2.Blood dyscrasias (Rare)
3.Hepatitis (Rare)
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