Ketotifen is very safe antihistamine used extensively in Europe to treat bronchial asthma and allergies. It is also being studied as a treatment for colitis. When used for asthma, weight gain and an increase in appetite are among the most frequent side effects. Ketotifen also protects the cells in the stomach, small intestine and perhaps the rest of the gut from a number of toxins. A number of case studies suggest that it may be helpful treating skin problems such as acne. Ketotifen also reduces edema (swelling and puffiness caused by water retention) around sores.
Due to the fact that clenbuterol is a beta-2 agonist/antagonist the downregulation of the cardiac, pulmonary and central nervous system beta-adrenergic receptors is an issue that users must combat when using this compound (3). A proven method to help alleviate this effect and ensure that the clenbuterol remains effective throughout its use is via the administration of ketotifen (7). Ketotifen is a prescription anti-histimines that acts to reduce beta-2 receptor activity. By reducing this activity, the receptor function is restored to nearly its original capability and the potency of the clenbuterol remains in effect. Doses of two to ten milligrams of ketotifen have been used by users of clenbuterol, but most would be well served to start at lower doses. It is unlikely that many will need doses higher then 5 milligrams per day. Taking ketotifen for seven days every two to three weeks should be enough to maintain well functioning beta-2 receptors and ensure that the clenbuterol maintains its effectiveness.
A normal dosage for ketotifen is usually 2-3 mg per day (two to three 1 mg tablets) to prevent the usual down regulation that is often seen with the use of clenbuterol. Some side-effects may occur with the use of ketotifen due to the drugs antihistamine properties. These include, appetite stimulation, weight gain, and drowsiness. But these are usually not seen often with the usual dose of 2-3mg per day used by bodybuilders.